That's good news about leatherseats.com, Giovanni. Did you get the suede inserts, or all smooth leather?
Elio, As for the World Upholstery stuff, here's where I'm at on those. My Spider currently has both carpets and seats sourced from them (according to the previous owner). They're both OK, but I'd prefer the original one-piece main carpet (and rear deck area, too), rather than all the small individual pieces. Some pieces really don't have anything to hold them in place, unless I was to use glue, two-sided tape, or screws, and I also don't like the look of all the extra seams and bindings. The seats may or may not have a problem that I can blame on World Upholstery. They're vinyl with the fake suede inserts. The vinyl really does seem to be very high quality, and it both feels and even smells like real leather. The pattern seems correct, too, so that's all good. But, at both lower corners of the seat backs (on the side you sit on), the seams are coming apart and the vinyl is tearing. Almost looks like it might have happened during the installation, which may or may not have been done by a pro. Might be repairable by a skilled upholsterer, maybe using reinforcing patches on the inside. I'm just not sure, because while all this stuff is <1 year old, I haven't had the car very long and don't drive it much, so it shouldn't be coming apart (neither the previous owner nor I are overweight or oversized for a Spider).
So, that's my dilemma, repair and stick with what I've got, or just do it right and forget about it, as this Spider is surely a keeper. I'd also rather have the original color tan seats and carpet, and I'm not sure why the previous owner bought all the new stuff in black, but it doesn't look as "correct" as I'd like.