I have tried a number of seat pads from the stock pad to composite pads on my RANS X-Stream with no success in eliminating discomfort that set in after about 27 miles or less of riding. That is, until I ordered some 2-inch, 1.6 lb/cu. ft (firm), open-cell, packaging foam from Foam Factory, Inc. (See: http://www.foambymail.com/CharcoalFoam.html). Rode 47 miles, today, in total comfort on a pad cut from this foam with an electric fish fileting knife. I experienced a slightly sweaty back, but I can easily live with that. Don't know how long a bare pad (no cover) will last, but at $10 per pad, not a big worry. I weigh 142 pounds. Don't know if this foam would work for heavier riders, but just thought I would pass my experience with it along. By the way, I attached Velcro to the pad with hot glue.

Quote from aikigreg on Apr 5^th, 2011, 9:09pm:

 
Greg, I've laid the seat back, and still had a problem. My butt is uncomfortable even on my Baron with it's laid-back seat. Until I made the new pad for my X-Stream, only one of my five bikes, the Carbent with Bacchetta foam pad, was comfortable. The new foam has just the right density in combination with the 2-inch thickness for my butt to not bottom out against the Hoagie seat mesh. So, I think that is why I'm not experiencing recumbutt on the seat, now.

Quote from aikigreg on Apr 6^th, 2011, 7:39am:

 
The thick Ventisit "comfort" pad was anything but comfortable for me. Too hard. Just shows how individualized pad selection must be.