It's your car, enjoy it.
Saying that a single auto loses to a bpu auto simply isn't true at all, a badly setup car won't fulfill its potential no matter what it is in any given situation without even factoring in driver ability.
A 1000bhp manual supra will drive just like standard around town - and make more power faster than a stock car, you just need to choose the correct parts. And no its not cheap.
Owning a single turbo Supra is great fun, and the noise is incredible. Keep the miles off of your original parts and go back to stock whenever you want, that will keep the purists happy too.