I also have found on mine (.40; .45 and .51), that they like to be run before dialing the Idle NV, they come set from factory with a reach low end, and that's great while it's in its breake in process, after several tanks, the idle needle valve can be reset and the engine will gain some power (great) and the transition from low to high will be smooth.
I also have found that they are great engines, I like them a lot. The only issue that I could find against them is related with weight (never performance).