Any absorbant is decent enough for plants. I took a look at some comparisons and although some things offer a higher concentration than others you won't notice a big difference at all!
Whichever you like best is your best bet. Flourite, Eco-Complete, Floral Max, Terralit or even laterite will work out just fine for any planted tank and sand will work, too (you'll have an easier time rooting the plants but a very small list of species won't grow quite as well)
Adding flourite or a sister-product will not save you from fertlizing products so don't think it's a way to get around the macro and micro nutrient problem =)
