Hi Tommy,
What purpose you are using fluro for? In case it is for jigging, I am for fluro more than nylon, mainly because of its higher abrasion resistance and soaking resistance (nylon loses a lot of strengh after several hours in water). But I know some experienced anglers who use nylon for jigging successfully.
What one should remember when using fluoro for jigging shock leader is that its thickness should correlate with the type and weight of the jig in order not to spoil its action.
As for brands , I used Duel, Varivas, YGK fluro for shock leaders for jigging and they all are pretty fine, though I like Duel Shock Leader Powecarbon most of all because of its softness. YGK Galis FC Absorber is also very good with the greatest "strengh to thickness" ratio among above said models.
DMV+ Nylon from YGK is also interesting for jogging, because it is said to have almost the same abrasion resistance as fluoro, but at the same time it is very supple thanks to its nylon nature, so not so bad for jig action.