Hrm... I like the 202/205 a lot and normally fly them oodles, but don't remember too much head shaking (at least, not compared to most aircraft). I don't think they're too horribly unstable, but at slow speeds they do have their moments. I flew one into the ground while I was in a P47D11 trying to stall fight with full flaps. I barely avoided stalling out, he didn't so it probably is there, but I haven't noticed it.
I'd like to see the 202/205 have a 4x 12.7mm gun option. I've got at least one book that mentions this was the common armament, and makes a note that it's about the same as the P51B. However, in Ah we only have 2x 12.7mm and 2x 7mm. The 7mm don't "do it" for me, heh. Yes 20mm are nice (and plentiful) on the 205 but once in a while I like to play dangerously