My experience comes from working on my SVO. My best numbers with a simliar IC that you have was 322whp and 346 wtrq on 26psi of boost and 31* of total timing.
later i changed JUST the IC to a procharger style IC (pic below) and ran the dyno again.
New numbers were 324whp and 379 Ftlbs WTRQ........... 24psi and 27* total timing. I felt alot better about turning down the timing a little and being able to make more trq with less boost.
Its all about FLOW......... a equal length exhaust header will flow better than a stock manifold, a bigger turbo will flow beter than the stocker, a big IC will flow more than a stocker............but there are trade offs the header might crack easier, bigger turbo means more lag, bigg IC might have restrictions for installation...........
Like i said earlier, AWESOME WORK, hell i need that kind of piping for the SVO, it just might not have gained anything for you.
If you have big plans for youer MS3 then pick up a Corky bell book, i'm not smart, i'm just able to understand and regergitate what this book is talking about and apply the info accordingly.
Hell i gained 32whp by just changing the exhaust housing on my turbo for the SVO. went from 243whp to 275whp trq dropped a bit, but then again i got rid of my bad boost spikes........
My svo has ALOT of dyno time (recommend using the same dyno every time for mods) Hell we did 23 pulls one day trying to tune the pig out. I wasted 8 gallons of racegas on the dyno lol. (wasted meaning... PIG PIG RICH)
But if you have specific questions i'l help out. I actually posted a LONG thread in the protege section for someguys that were wanting IC setups.
Heres the IC thread