Plenty of folks not using flouro, but I'm not one of them. Does it make a difference ? I've become rather fond of flouro's abrasion resistance. However, I don't buy into the whole invisible theory, nor the fast sinking claims either.
Specialty "tippet material" is a bit more refined (slightly more consistent in diameter throughout the spool, and is wrapped onto the spools in a way that avoids twists, minuscule kinks, and anal crap like that) and I do use it on 5x and thinner stuff. But for anything 4x and heavier I do fine with Trilene 100% flouro, or P-line Flouro and buy it in 250-300 yard spools.
The greatest thing about REAL "tippet material" is the handy little spools.....So much handier than carrying a 250 yard bulk spool around.
So I buy and use just enough Rio Flouroflex Plus @ 15.00 per 30 yards so that I have handy little pocket sized spools to refill with "other stuff".