I hope you pro legal license guys do realize that Reiza Studios are actually doing a similar thing...
Regardless of the ethics... I have the Cayman GTS. Haven't spent an awful lot of time with it but here are my thoughts:
-the 3d model is very good, but not Kunos quality level (the textures seem to be lacking)
-the engine sound is the weakest link, sounds more like a V8 than flat six
-the driving experience is a mixed bag. The car reacts more or less as you'd expect, but it feels generic. Also it seems like the engine performance is a bit off - there is a huge torque spike above 6000rpm
Just my first thoughts. I'll chime in again after spending some more time with it. Really wish that engine note wouldn't suck so bad though...