Second season on an HM turbo 12' pro. It has 2000 miles now, 1400 of them with boost running 6.5psi. I am hooked and wouldn't hesitate to do it again. As I am sure you know the biggest thing when entering turbofagdom is do it right from the start. Boosting a sled requires the rest of the sled to be on par with the power, bigger injectors, proper fuel, skid, track, drivers, chain drive (or upgraded belt drive,) etc etc. I have slowly been adding these things but if I were to do it again they would be installed before hitting the hills.
Personally pistons every 1000 miles (a season for me generally,) after 3k miles the bottom end will be going to Indy Dan. Heli bills are expensive, maintenance is important.
The Pro Chassis is epic, I said from day 1 coming off an XP 'I don't care how many motors it needs, it handles so well.' My friends run the wheels off theirs every year and flip them at the end of the season, I fix/upgrade mine, we are probably even investment wise at the end of the day.