I replaced my original seats with some LeMans from http://www.classictouringseats.com... Mini review below.
Overall cheaper than alternatives and in person very fine quality. I previously bought some "secondary" brands for other cars and more than once been disappointed with the finish of the stitching, piping, or the downright unprofessional look of some covers being stretched funny (I mean anything below Recaro or Sparco - let's say brands like Corbeau or similar - yikes). So I wanted to see what I was getting before spending $...
The warehouse is in SFO and I wanted to sit in them in person to make sure I fit.. Upon chatting with the owner (a porsche nut like us) it came up that we live near one another so he kindly offered to bring up a demo seat for me, and even a pair of seats with all the goodies should I want to buy - no pressure... I loved them and I did... Excellent service and no shipping ;-)
Installation was easy overall... You reuse existing rails bolts for the adapters and the supplied hardware for everything else. No issues at all.. Except seat belt attachment points on each side. The ones on the adapters are not identical in design to the Porsche ones, so the existing Porsche bolt could not be reused and I could not find anything matching... So I made do with some trial and error but you have to have the right kind, pitch and length to not block the seat movement.. Turns out something like 7/16 pitch 20, about 1" long does the trick... Just putting that here for searchers.
As you can see from the pictures, the new seat is slightly lower than stock in appearance (good) but in fact for now I sit higher because "new foam" vs "old destroyed padding/springs" ;-) My body weight will soon resolve that I think.. Very happy with the look, the quality, the price, and the service... I can't compare to vendors I have not used but really those things look perfect from all angles and I believe the side bolsters aren't quite as wide (into the seat back) as the Recaros they are based on, allowing people over 200 lbs to still fit - LOL. I'm 220 and I fit !!!