Expanding horizons.
Let’s do Chicago for the day or the weekend becomes let’s do Dallas for the day or weekend.
It’s a great thing!

If you’re at Smyrna you’ve got a bunch of good resources for money saving MU2 ops. Including maintenance (Mike Noblin and his various contacts), avionics (Carpenter), training (Reece) all on the field. Fuel would be under $4. Most FBOs don’t like you using the contract cards at home base so you typically negotiate a discount directly with your home base FBO, but of course you have the knowledge of what the contract costs so you can usually do at least as well if not better.

I’m don’t claim I own and operate my Solitaire for what Tarver is claiming, but he’s close enough I think it’s plausible given regional differences, I have about the worst regional costs. My hangar is $1150/mo, I pay local property tax of 1%/year of hull value. I insure for $750k hull and carry more liability. The -10 solitaire burns more like 80 gal block but gets 300 kts (call it 285 block). The 4 blade props require overhaul every 7 years (3 blade do not). I do have to travel farther for recurrent. But it is still less to operate than my buddy’s 425, for example.

Re your turbine Duke idea... In my estimation, having a plane designed from the outset to be a turboprop will be vastly superior in both cost and performance to having a turbine conversion. The piston planes just weren’t built for the job, don’t carry enough fuel, aren’t quite beefy enough, etc. If you are going to go turbine, I don’t think you save anything with a conversion and you will generally have a difficult time getting stuff done to it since it’d be a one-off. If you love to tinker, then great, maybe that’s the goal. But if you want to actual use and travel with the airplane, I would get a model that’s built for it in the first place. I like my MU2 but recognize it’s not for everyone, but I’d still get a built for purpose turbine.

I won't voluntarily fly a piston single again in IMC or at night or in mountainous terrain. Ever.

Only takes one trying to kill you to cure you of that. I'll pay for the extra fuel.

Another thing to consider is how you’ll interface with HSI and OH in a turbine. With the legacy models, like a MU2, the capex is relatively low. So, values aren’t hammered as hard for time left on engines. Depending on the hours to HSI or OH, they might never come into play. HSI and OH are once in a lifetime events for an owner that flies low annual hours. Sometimes those costs are a non-factor. Not always, but sometimes.

Yes, there's an MU-2 in the area for $175k currently flying with great avionics, decent P&I, but high time engines that we'd get 20 years of usage at our usage rate before we had to do the engines. I'd be 68/69 and probably looking to downsize - who knows what would be available by then in terms of GA.

There's a second one that has "decent" avionics (same as Laz actually) that we'd never hit HSI or OH at our usage for $240k that they can't move and probably go lower, good P&I as well, but it's out in Arizona.

Capex on the earlier short body models is certainly reasonable.

We just got Laz and I'll want to fly him a year anyway and work out the kinks, get an engine monitor and such in, etc, but if I could get $140k back out of Laz when everything is perfect and flying regularly with these low-time engines, it wouldn't be a stretch to move to $175k, maybe even the $220k-225k range.

Good to have options and the knowledge now to make a good comparison. If I could just get that company up in WA to let me bring a donor MU-2 and put Garretts on the Duke as part of a new STC...

Just sayin' it's a lot cheaper to put used Garretts on something than it is two brand new PT-6's. There's probably a better market there for them. Wonder what their all-in profit margin is on the Grand Duke conversion...?

Although on the other side I flew about 120 hours in my piston single last year. This year 130 so far in the TBM.....

That’s so true, but consider it a gain. I flew my Bonanza 100hrs/yr. I fly my Mustang 200hrs/yr. Most of us don’t have an airplane to not fly it. (Please pardon the double negative)

I'm with Jon, I think you would be way better off buying something that already has Garretts on it. Even if you get a sweetheart deal with the Grand Duke folks, you're still going to end up with a plane that wasn't designed to burn kerosene.

With that said, one thing I noticed about the MU2 is that my skills had a shorter shelf life than any other airplane I've flown/owned. I could take a month or 2 off in the 340 and still felt comfortable getting in and launching, but the MU2, for me, required more diligent attention to keeping current. If you're going to fly it for less than 75 hours per year, it might be an issue. When I wasn't flying every week and the plane had sat for a few weeks, I would go out the day before and do some takeoffs and landings and knock the cobwebs off. Anecdotally, I've had several fellow MU2 owners express the same feelings.

YMMV

That’s the nature of higher performance airplanes.

I try to fly my MU-2 weekly. I can’t think of any other airplane where I couldn’t go months and not be ok launching off into bad weather. MU-2, not so much.

Going back a few pages to Stan's point.

I'm wondering how much mentor time would be needed to go from VFR-single engine-piston-low altitude to IFR-multi-turbine-high altitude-more pax. Each one of these has many aspects - IFR being the greatest (IMHO). Multi is pretty easy to learn. Turbine - easy to learn, a jet is a little tougher but still simple. Managing more passengers can be interesting - I've learned to have help back there. High altitude goes along with IFR but it incorporates a different approach to WX avoidance compared to a SE piston.

Experience happens with hours but the relationship is related but not direct. As pointed out by the OP, flying around in circles to check boxes has limited value. Value comes from taking on something new and sometimes screwing it up. The key here is to only go so far as to get fully "whelmed" but not overwhelmed. Once an event happens, you reflect on it, figure out how to improve it then wait fot the opportunity to try out your new improvement and see how it works out. This make take a few tries before you are happy...

My solitaire was about 115k to fly close to 200 hour in 12 months. That’s every penny including very expensive hangar and expensive home base fuel.

Tarvers number is doable if you live somewhere with low fixed costs.

I doubt there is any tprop that can be run for less than mu2 if fuel prices stay close to current.

I

For me (and several other MU2 owners I've spoken to), the MU2 stands out in its need (demand) for currency.

I’ll add my agreement on the need for currency. I typically fly about 4 to 6 legs a week in the Mits and when I’m away for a couple weeks on a vacation without the plane, I move a lot slower and more methodically the first flight back to make sure I don’t forget anything. They are remarkable planes, but the panel looks a bit like something from an old 1960’s military plane (in my opinion)...complex engine starts with lots and lots of switches, gauges, and things to test before you even move. The King Airs seem pretty simple by comparison. But once you are airborne, compared to my prior pressurized piston twin, it is a remarkable aircraft in that it mostly takes care of itself. Fantastic weather/snow/ice plane with heated intakes, heated glass windshields, and automatic boots on timers.
Much like some others with -10 engines have posted, I see more like 80 or 82 gph in winter but also usually 310 to 320kts. Fuel is $1.50 to $2.00 less than 100LL in my area. My plane burns 20% more fuel than my Aerostar 601-P/700 did for a given distance, but Jet A can usually be purchased for less than 80% of AvGas costs so the DOC in my case is lower than for the piston twin. Maintenance intervals are also usually less costly than in the pressurized piston twin, but they happen more often (100hr inspections are required in the Mits while the piston could go the whole year with only an annual inspection) so the maintenance costs are a bit higher for the turbine. But the fact that it routinely flies 100 hours between inspections with no issues (I’ve never had to have a mechanic come to my hangar for the plane in more than 3 years) is worth a lot of money to me. When the plane’s a business tool and must be used on a schedule, multiple times a week, the extra costs of the turbine engines and bulletproof systems pay for themselves pretty quickly.

Something I would highly consider is that you wouldn't want to be in a turbine airplane that you can't financially swallow an unexpected catastrophic engine problem. While I too have put my dollar votes toward the turbine (for all the reasons I used to argue against), you have to be able to absorb the (extremely rare) occurrence of a thrown turbine blade giving you a $100,000 uninsured event. The next step of that problem is if you have a nearly depreciated older airframe, you;re putting that money into an assert that won't appreciate enough to cover the money you just had to put in to keep it airworthy.

Engine issues like that may be very rare, but the occurrance rate is greater than zero.