I can not speak about the LSeats.com Porsche seat replacement covers but I bought them and installed them in my 2003 Miata. I was very happy with them. When I took them to my upholstery man (35 years experience) he asked me where I got them. He said that he could not make them for what they cost and said that the leather quality was very good, in fact he was going to try to become a dealer for them. He installed the seats and rebuilt the side bolster foam. They came out looking great. This being said if you are interested in a set from LSeats you should call them and ask for the color samples to be sent to you. I did this as the guys on the Mx5 forum had said that the light tan color they had was not a perfect match for the factory Mazda seat. They were happy to send me their color samples. The color was not a perfect match for my slightly sun faded Miata but I ordered them anyway as there were no other alternatives out there that was a perfect match. That was a year and a half ago. The seats still look great and I get compliments all the time on them. No one has ever said a word about the lack of a perfect match.
I have a Lexus SC430 with a Ecru (off white) interior. The guys on the SC430 Forum that have ordered replacements for their Ecru seats said that they loved the seats and that it was a perfect match for them.
The color in the picture is really not as far off from the stock as it looks. The color samples were exactly the same color as what I received. I would recommend them but get the color samples first if you have anything but black to see if they are acceptable to you.