The F1's and Slipstreams aren't negative, at least not measurable so, so no advantage against top heavy. Doubles can be kicked around barefoot but you're not going to make any land speed records.
That being said, why are you wanting to dive doubles? If it's for the extra gas, then just buy a steel 130, if it's for redundancy and all that then that's fine but you're not going to want full foot fins... Generally speaking the jetfin style fins are very difficult to do a flutter kick with unless you have real strong legs. They don't bend much so the extra resistance is noticeable and can cause some wicked cramps if your legs aren't used to it.
DiveRite has some new fins that are pretty light, but stiff enough to move a set of doubles. Real nice fins if you don't have to kick against currents and what not. I have never found a set of fullfoot fins that were comfortable and I don't like the idea of having to buy a set of open heel fins to dive in moderately cold weather either. Just get one good set of fins and you're set for most things.