MTN or road? What you riding?
Either way look into Specialized Body Geometry saddles. The Avatar and Alias both some in 3 widths and have a cut out for pressure relief on soft tissue areas. They are very comfortable. If you want a little more padding, look into the Telluride by same company. Basically anything with a groove with help with numbness/erectile dysfunction. There are studies that show Specialized allow for the most blood flow.
http://www.specialized.com/SBCEqSuperSection.jsp?ssid=Saddles