Well, personally I own 3 pairs of sleeves, don't ask why.
White Crusher 3 ply Knee Sleeves in a size L
White Crusher 3 ply Knee Sleeves in a size XXL
SBD Knee Sleeves in a size S
SBDs cost nearly double of what the White Crushers would cost but I would say they're well worth it. When it comes down to it, it's all about sizing. Tighter fit for more "rebound" and a looser fit for general all around comfort. I've not tried all the various brands but I do ask around, I'm kinda a gear whore like that.
From what I've heard...
Sleeves that seem to aid more in performance would be the SBDs and STrong sleeves.
Sleeves that aid more in comfort would be the Slingshot Knee Sleeves, Tommy Kono Bands and the Rehbands.
As far as I know, the Slingshot Knee Sleeves and Rehbands(referring to the standard blue 7mm ones) are almost identical.
This are just some of the more popular brands by which I've been exposed to.
This was from a week ago, you might want to take a look at it.