I'm not sure, sorry - I didn't purchase SW2, skipped it straight for SW3. For the exact same concerns on stability. Kind of annoyed though since I heard there's a random mission generator in it which SW3 doesn't have although I hear SW2 is short even for a Star Wolves game.

Dunno how bad it really is, some people have apparently played it quite a bit plus the earlier modding scene was based around SW2.