These are the same sticks as are in the x-arcade controller. Don't buy them if the bid goes very high--you can buy them right from the x-arcade website, or you used to be able to.
I've heard people here compare them to the Happs supers, but I don't own either, so there you go. I personally am inclined to stick with what's more standard and what people know (and have hacked, etc), but hey, I'm a coward and I admit it.