i had a 543rf with an etec 130. My only gripe was that i didnt get a 150. The extra 2 cylinders would have made it sing. That is something i would always insist on with signatures, get the max hp allowed. The hull is far far more competant than i am brave. The only greeny i coped was because i got scared of the next wave and pulled back on the throttle instead of powering on. The ride was great. You just had to get the weight distribution right at times but trim tabs would fix that in a jiffy. As for stability, its definitely not tippy. 4 of us fishing on one side without a drama.
the anchor well has a narrow opening for a drum anchor, a bit of a cut and that was fixed.
The finish on signatures is pretty good compared to others, just not perfect in some-places. No boat is totally perfect, lol.