Neon seats, hands down, IMO.  I have the ones from the Plymouth Neons (2000 and newer, I believe), and they have more padding and are nicer looking seats than the older ones.  The samurai seat rails bolt right on to the front of the neon seats, for the seat rail attachment on the rear, you can use self tapping screws/bolts to secure them (or you can use bolts and nuts, your choice).

I have no idea if they fit but seats from a Wrangler TJ are some of the most comfortable I've ever sat on.  Even the early ones.

I'll second this one. I got two Jeep seats from a local "you pull the part" junk yard. They were mint condition. $30 each. I had to make some flat iron rails to adapt them to the Sammi rails, but they are so comfy. I'm short so the slight increase in height was not an issue, but might be for some of you tall off roaders. Now to find something for the back seat.

Found a Samurai for sale on Criagslist that was using powered seats out of a Porsche Boxter.  Those are probably rather comfy.

Cool, Right now I'm sporting some original Sammy seats with the custom hefty bag seat covers. Clean up is a snap