I've bought more expensive headphones since owning the HD58Xs but alwys come back for their superior audio and comfort, greatly in part because of the pads. Although after about 4 years of heavy daily use I needed to buy a replacement
I bought these for the HD58x. You lose so much detail compared to the stock pads that I cannot recommend these at all. They are much thicker than the stock pads which is probably why you lose the detail. I can say they're very comfortable, but they change the sound way too much for my liking. I was really hoping for an exact replacement of the stock pads.
I got the sheepskin to replace the factory pads on my 6XX. There is a very noticeable difference in the amount of bass and mid-bass after installation (Huge increase). I think it's a great change from the normal 6XX sound signature but definitely choose velour if you want to keep the 6XX as stock as possible.
Got the perforated sheepskin version and switched from the factory velour. I like the velour and bought the new ones just to try them. So far, they are very comfortable, I actually like the feel better than the velour and they seem to be slightly cooler. Mainly, it seems as though they let in less outside noise with music playing than the velour ones do. Haven't noticed a change in EQ.