First of all, the engine on the RV-10 turboprop was called the PBS TP100 and BPS is very much alive.
Data I’ve seen that includes all components needed to run the Turbotech TP-R90 engine show the weight at 163 pounds, so about the same as a 914 turbo or 912 iS with a max of 135HP. The installed weight of the PBS TP100 is 157 pounds at 241SHP. In the RV-10 they were seeing 180 knots true but burning 18 GPH. Eco cruise was 14 GPH.
The heat exchanger is definitely a game changer with the TP-R90 and the four individuals who started this company definitely know what they are doing. There’s a really good article talking about the engine on page 64 here.
https://www.ust-media.com/ust-magazine/UST031/64/
In terms of reliability sure there’s not a lot of data on this engine yet, but a single compressor and turbine wheel inherently is so much simpler in operation vs the 915 I’d feel much better about its reliability. I think the started 3000 hour TBO is evidence of that in comparison to the 1500 hour TBO on the PBS and 1200 of the 915.