I have a friend who's going to be at Disney during our upcoming spring break (I may be there too - just waiting for airfare to look better than $500 round trip from BWI when it's usually less than half that, or at least about $300). She owns DVC and they're going to be at the Beach Club followed by the DVC at Vero Beach.
I don't know what time of year you're looking for, but it looks about an hour south of Cocoa Beach?
I guess the con is that yes, it is the Atlantic!
Pro would be: it's a Disney resort, so while at the beach, you'd have that Disney feel to it.
I've never been there, so can't comment on it at all.
I have spent time as a child on Sanibel Island - it was so nice and quiet, fun to just bike around and collect shells. My folks spend the winter in Naples, and although my sister goes down most summers with all her kids and uses the house (has its own screened in pool) and she finds lots of fun stuff for her family to do and enjoys Vanderbilt Beach, I don't particularly love Naples. Matter of fact, I haven't been there is 12 years! And I could go use their house in the summer for free. Just not really interested.
Honestly, after living in Hawaii, I would rather do Disney in Florida and save beaches for there or the Caribbean. And I live near Ocean City and have never been!
I do agree though - I would prefer the gulf area. Naples is a good 4 hour drive anyway - St. Pete is a cool city though! I'd definitely find things to do (but I'd want to do museums and Busch Gardens LOL ).
Just wanted to throw out that idea of the DVC resort too!