You say you dont have any problems with the Evo, but more stability would also be a positive change, which is it?
![:) :)](/media/kunena/emoticons/smile.png)
(I mean that light-heartedly)
You should consider a more stable boat if
-You're missing days because its too big but you'd go if you had a stable boat
-You're missing waves because you're bracing or wobbling instead of sprinting onto them
-You're not having fun ("Fight for your life/scared/nervous, stability wise", instead of "WHEEEEEEE")
-You're early in your downwind career. Downwinding is very complex and linking runs requires nearly full attention even when you know what you're doing. If you're focused on stability your DW surfing will immediately suffer. ZachHandler reported his all time fastest mile on a V8 doing the Molokai. He paddles K1 all day but had his fastest mile ever in a V8. When DW'ing, its all about surfing and linking sets, much more so than a skinny boat.
A skinny boat only makes you faster if your foot's on the gas the whole time.
That said, the skinniest boat you can have fun in is often the funnest boat to be paddling. The key is to paddle the skinniest boat that fun, but not get caught in conditions that make your boat too skinny (i.e. Fun becomes Scary). It can be a fine line, and much less of a problem if you can justify 2 boats, an elite for small days and a stable one for big days.