Just bought a couple reels off of ebay. One of them came spooled with some very bold dark yellow line. I don't know for sure if it's mono or flouro. It does have memory, but not like the cheap mono junk on it's twin brother. I like the way it casts, and would like to figure out what it is, so I can buy some in a less visible color.
It feels stiffer than mono, but when I tied a weight on to test with, it took an improved cinch knot without any noticable weakening. I tried pretty hard to break it.
It also acts alot different in a backlash than from what I've seen from mono.
I've never used flouro before, so I'm curious.

I dont know what kind it is but if it came with the reel, I wouldn't trust it. For bait casters: Flourocarbon, I use Seaguar invisX or the red lable for economy. BIG GAME is good for mono if you respool every weekend with fresh line. Buy it in bulk and enjoy the savings. For my spinning reels I use the new Berkley Nanofil for awesome casting distance. Braid: most my buddies are stuck on Power Pro, but I like the Sufix 832. It has a slick finish that is good casting straight outta the box whereas Power Pro needs to be broke in before it cooporates. My take.