Man you love posting in ever turbo topic here!
Anyway, the true issue is dynamic compression. Without better pistons it will eventually break something. Tuning helps for sure, but it tuning alone can't completely make up for the ridiculously high dynamic CR caused by the stock piston face.
Pop in aftermarket forged dished pistons, and now we're talkin.
Rods are the same as the stock WRX which can take up to 20 psi boost on stock internals. While I'm not saying that the 2.5RS can do the same, I am saying that the rods will be for the most part, just fine.