just my opinion... but,
if you are going to turbo your car and try make 2 or 3 times the amount of power from a stock motor, reliability will always be an issue. if you want reliability like OEM, then dont mod the engine especially turbocharging it.
like i said before, if its tuned right then i dont see any problems. we had a b16 turbo and nitrous daily driven 2 years ago and it drove fine...then a 100shot nitrous gsr hatch that ran for 2 seasons without any problems.
whatever the hp is that you make....it seems people keep thinking you will drive around with that much power ALL THE TIME... Yes, 300whp will be on tact when you Full-throttle it to redline but not everyone will be driving like that "DAILY". If you do, doesnt matter if its fully built or stock, it will go.
With the K-series.. IMO, i think its proven that it can make power. i mean over 850+whp, 10,500+rpm shifts, attending NHRA and NDRA events as well as running mid 9's or better at 160+mph consistanly......it will break a motor LOL... that was a pretty long run-on sentence.
Again its just my opinion....