Thanks guys for the positive reactions. I'm 100% that I dont have the desire to build the engine. I also love twin turbo systems but it's not for me. I want to throw some money at it and include all upgrades like clutch, fuel system, blabla) and call it a day. I don't consider the RJM kit either, dont want to cut the hood.
So I have been doing some research on all the SC kits and the BP kit and created an overview of the average power output of these kits. I collected some data and tried to make this as comparable as possible. So only 95 or 98 octane (called 91/93 in usa - but it is the same) and no race gas pulls. All cars tuned at Specialty Z to compare the same dyno.
Ofcourse there are many many factors to take into account which my overview doesnt, but i'm just trying to keep it simple and needed to create a rough guesstimate for myself.
The GTM stage 1.5 is not in here, but i believe it's performance is very similar to the Topgunz kit.
So I doubt whether the stock block can take 12 psi and that huge mountain of torque of the BP, especially since I want to be able to brainlessly beat on it in the Eifel region here. Otherwise it looks like the BP just offers the torque that the SC doesn't - which makes sence - so it all comes down to personal prefference.
$-wise proceeding with my build with either the BP kit or TopGunz kit seems to be within ~1k $ of eachother.