Seen the results of 3.0 with RS's and -5's on the same engine. Its not even fair, actually it's a joke.
If they're lacking top end it means your setup was ineffecient/shit.
2530's/-5's lacking top end? Rightio. 450 on my engine was only a intake can twist away but I didn't want to loose midrange.
My 2.8 results are enough. 125 kw extra through the midrange and 25 more up top.
Gav made more midrange with 5's and made the same up top (the went onto make 620 rwhp).
It's a discussion/argument that's been had many times.
"but I'll feel you in with my peak Powah".
Yep....
Average power > peak power.
Whatever makes you happy...