Howdy - I really enjoyed flying the A6M3 in Fighter Ace Realistic (As I remember) and Warbirds back when, and I was quite happy when I saw it appear some years ago in AH. The joy was short lived, however, because the AH A6M3's roll rate was the same as the A6M2 and the A6M5. In AH it does exhibit a faster climb rate than it's brothers and there must be some reason for that, but I didn't see it mentioned in my search for the improved roll rate.
With it's clipped wings it displayed a faster roll rate in the other Combat Flight Sims than it's brothers. I have done some research over the years and encountered several sources that mentioned that the A6M3 had an improved roll rate, but did not perform as well as it's brothers at high altitude and, for some reason, had a shorter range.(?)
It was however, a real joy to fly.