Well, I have actually owned two Soloy converted aircraft. Fuel burn is 22 gal an hour, 5 gal more than a TC aircraft (17), but at a much higher IAS (152 kts). So its specific fuel consumption is not all that higher, but burning a fuel that is $1 cheaper per gallon and available worldwide. Now the conversion comes with additional fuel capacity in wing and Soloy's STOL mods. So gets in much slower & shorter, goes actually further in range than a TC aircraft at a higher IAS. I would routinely cruise non-stop from Miami to La Ceiba Honduras at 22,000'. Not going to get that from a regular T206. Yes, bring buckets of money, but I only paid $135,000 for my second one (some parts required). You just have to love sea level to 10,000' in 4 minutes after a 600' ground roll. Turbines really do not mind running at the top of the green arc, so no having to lean out and you can come down like a rock, since shock cowling is not an issue. Having Beta is kind of a plus on a seaplane as well.
I really do like the installation of the Lycoming much better in the H model. Yes Cessna owns them, but it really is much cleaner install and it has needed far less maintenance than my Continental equipped ones did (G models). Just winging the price, I would say if you have to buy engine (550N), install kit and STC you are in the low six figure range. Aside from the issue, you will most likely come up with a prop incompatibility issue, which would increase the price a bit. An issue you may find with an equivalent Lycoming conversion as well. One issue with the 550N is an issue with cowl interference, so I think any 550N STC would necessitate a cowling mod as well. The cowling on the Lycoming install in the H model is different as well. All conversions start you down a rabbit hole. When you change the cowl, you need to re-do the spin testing, which means more costs. So the STC and the kit costs more.
Most times, engine conversions of any kind do not tend to be reflected in the sale price when you decide to sell the aircraft. So you will not come out ahead on any conversion. There is also one other side effect of conversions, when you sell; you have to sell your airplane and the conversion at the same time. So it makes it just a bit more complicated to sell from a marketing standpoint.
So many tradeoffs and benefits. Choose wisely Professor Jones.
