I had a Serfas in the early 90's and loved it. It was gel, with large cutouts and a sort of magic material suspension in the cut outs...

A bit of crash damage and the cover was failing. Afraid I couldn't find an equivalent.
But Serfas are still here! And it seems the RX is it's great-great-great grandson!

I have a Serfas Rx as well. For me, It is marvelous!