Well, I've driven both and own a Club Coupe. X51 IS NOT marketing hype, which to me implies all they added was a fancy carbon fiber intake and exhaust that doesn't improve the engine.

The X51 is a noticeably different in that it launches quicker, and the engine is much more responsive than the standard 3.8. When Exellence did their cover story on the Club Coupe in the February 2006 issue (linked below), they gave a really objective viewpoint. IT IS expensive, but factory power always has been with Porsche.

I wouldn't trade mine for a 997S with any tuner's package.

Also, I always marvel at the paradox that Porsche went to all the trouble of adding (in X51) a larger throttle body, optimized intake, cylinder heads and exhaust manifold modifications, in addition to the airbox, ECU mod, and exhaust. Silly Porsche--the tuners know better and can deliver it with an airflow kit and an ECU tweak.

With an aftermarket tuner, I am sure you could buy similar or better results advertised on paper for less money--but will it be as driveable, will it actually do what the tuner says (e.g., are you getting an engine dyno as proof), is it warrantied, and will it give you an engine that doesn't lose power and torque somewhere along the engine's rev band? You know what you get, for certain with X51.

Also, X51 purportedly delivers more than the advertised power--FWIW, folks who are supposed to know have written here and elsewhere of X51 engines dynoing at 395 HP which I'd believe from a seat of the pants perspective.

BTW, there are a few Club Coupes advertised for sale, but I don't think they're going for a discount

a 996 GT3 would be a tempting alternative, or a 997 GT3 which would give you 415 HP and the true dry sump 3.6 GT 1 based engine. Or just stick with a base 997 S (as long as you don't drive an X51 and find out what you're missing). But me personally, I'm leery of tuners on normally aspirated Porsches.

X HITS THE SPOT