This thread seems pretty polarized in opinions on the matter. I firmly believe that the people that live in areas of general good seeing have no idea of how BAD seeing can be in general and that is the reverse for people that live in areas of generally bad seeing.
So yes the people that enjoy generally good seeing will of course almost always benefit from a larger aperture. Where I live I cannot use over a 5" scope to its full potential on anything more than a handful of nights a year. I have compared all kinds of scopes on the same night side-by-side and on the average night of seeing here in the NW a good 5" APO is about as good a planetary view as you will hope to get. I recently spent a night comparing a SV130EDT to a Meade 8" SCT and a 7" Meade MAK on Jupiter and Saturn. The seeing on this night was not great, but also not bad for my area(I suspect that you fine folks in Florida and other areas that enjoy good seeing would concider it as "bad"). The APO provided hands down the more contrasty and EASY to pick out the fine details view. That's not to say that I than could not go to the larger compound scopes and after some study not see the same detail, but it sure was much harder to see them.
In the above comparison all the scopes where allowed to cool for at least an hour. Witch brings up another can of worms... I don't think that people realize that an SCT is almost impossible to get to thermal equilibrium in some areas of the country throughout the night. It just never gets to its sweet spot in performance. It certainly does not if you take if out for my average 1-2 hour long evening viewing session of the planets(yes I know about insulation, but the vast majority of people to not insulate although I do want to give this a shoot at some point).
Anyhow, not trying to step on any toes just another data point!