I've never used regular Flourite, but I do have Flourite Black Sand. I also have Eco Complete in a different tank (this one is also mixed with some regular gravel and laterite).
I really liked that I did not have to rinse the Eco, even though adding to an established tank. The Flourite Sand, like all sand, was a PITA to rinse out, but it looks very nice. Both seem to be very good for my plants (Echinodorus bleheri "compacta", crypts, HC, Ludwigia glandulosa, etc.).
I personally think it is a draw between the 2. If you don't want to mess with doing special cleaning for sand, then I would not get the Flourite Sand (but then you didn't mention it anyway). The Eco does tend to send up blooms of dust clouds when cleaning (but this might also be the mix of substates I have in that tank). Again, I have no experience with regular Flourite, so I cannot comment on it.