BK 3,7 more closely resembles the A-10 ballistics of today. While the NS-37 had an impressive all around performance for WW-2 it lack the penetrator head of German ammo and the higher velocity. I too have gone thru 200 rounds of NS-37 ammo trying to punch thru a Tiger-2 and I just dont see how a Stuka could be worse. Most of all its designed as a verticle dive bomber and should get you the better angles.
If we still had F3 I garuntee you I'd be punching thru Tiger-2s with NS-37s. The trick with the Stuka will be to get in close and fast, get a few rounds off, and reconvert the energy for another pass. You might even be able to invert and dive. I'll be setting my convergance for my 87G very close, as in 200 to 250.
It only takes one or two rounds to disable the tank.