I was going to post that I have some sixsixone gloves that have lasted for eons, but I noticed putting them on this morning that the leather on the heel of my hand is starting to wear through. These have outlasted every other pair I've had. I think the difference is that the leather is kind of a suede rather than a smooth finish so it seemed less susceptible to rotting from my sweat. The entire underside of the glove is made out of leather which I think has made a difference as well, gloves with fabric on the underside seem to deteriorate in a matter of months for me. Finally the padding in these is layers of padding (fabric I think, or maybe leather). YMMV

My gloves get a weekly wash to keep the stank somewhat under control. I also leave them on the bike when parked at work.