I believe Flourite is a substrate that promotes good ion exchange, meaning it absorbs fertilizers from the water column and makes them available to the roots. The root tabs might be redundant, but they'll only help. Just make sure to bury them well.
Swords are heavy root feeders. I'm not sure about crypts. I've got Crypt Lutea and Crypt Parva in a 20H in PFS with no root tabs and they're growing nicely. The Lutea has put out maybe ten new leaves in the couple weeks that it's been in the tank. I've got ~30W of T5 (not T5HO) light and I dose Flourish every PWC.
I've heard nothing bad about Flourite. It's just too expensive for my tastes. When funds permit (after Christmas), I'm going to pick up some dry ferts and start dosing my tank. I have Black Blast, a $9 for 50lb blasting compound, in my 40B. The MSDS shows it has a similar makeup to the house substrate from aquarimplants.com. I want to see if it will absorb nutrients and promote growth like the Fluorite.