MTB saddles tend to have a bit more padding because in general the riding position is more upright...a full on XC bike this may not be the case but in the majority of the MTBs it is. The Specialized line of saddles is REALLY good. Go sit on their ass-o-meter and get the right width saddle...I have 3 different styles...all Specialized and all the same 143mm width...I could ride all day on any one of them. The Rival is a nice MTB style saddle and I run it on my MTB and my commuter, the Avatar goes on my fixie and my beater roadie and my Merckx sports a Toupe.