I had them in my Boxster for 3-4 years before I sold it and they held up very nicely. I assume they are still in it but haven't kept in contact w/ the buyer.
bought mine on ebay but look to be identical... back then they were only $55 though... before I think they got the cease and desist from Porsche
Couple of tips...
- start w/ the brake pedal - it's the hardest to install (b/c hardened steel) but the one w/ the most limitations for placement. Then line up the clutch (plastic pedal) off of it
- if they don't come w/ lock washers, add some and some loc-tite. You don't want them loosening up and coming off while driving
- use a small mirror (wife or gf's cosmetic mirror) to see what you're doing on the back side.
- mine required the original pedal pads to stay on for final attachment. Use masking tape on the OE pad surface to mark hole locations (check back side for clearance). Then drill thru the pads to mark hole in pedals. Remove pad covers to finish drilling in pedal. This will give you a punch in the pedal's surface to help prevent bit wander in the hardened steel. (lay down newspaper or a drop cloth in the footwell so you don't have to vacuum out drill bit shavings either...unless your floors need vacuumed too
)
- to really finish them off (I never did this though) you could pick up some similar rubber, cut circle to size and super glue them on top of the screw heads...
Good luck - there are some more extensive DIY write ups around here somewhere so door a search
PS- I think they look really good in 9x6 series cars. Seen them in some 9x7 series and to me for some reason, they just don't seem to flow as well. Thus I haven't put them in my 997 but to each their own.