With a single you make a merge on the hot side. With twins you make a merge on the cold side.
Yes it spools instantantly but it’s in a boat in front of a jet and there is always a ton of load. On the dyno we started the pulls around 3500 and it was in boost right at the hit. The turbos have billet compressor wheels, new gen turbines, and ball bearings, so all the crap to make em spin up fast.
What is your total power goal? And how much power does the engine make NA?