I would like to test a Cayman S next. How does it compare?
A stock Cayman S has a very well sorted out suspension, it probably has about 20% more grip than most NSX's with suspension mods even with street tires.
The 2nd generation Cayman S's have a Direct Fuel Injected Engines that are good for 320HP at the crank, with some exhaust mods there are 2nd Generation Cayman S's that are putting down close to 320 to 330WHP about 350~360 HP at the crank.
The 2nd generation Cayman S's can be ordered with a LSD that was missing from the 1st generation and makes quite a bit of difference (the NSX came with a LSD that is ok for most non FI applications)
Overall driving dynamics/feel is very similar to the NSX but with more grip/bite and waay better brakes than the NSX. There is no snap oversteer on the Cayman in stock form.
The NSX is severly limited in regards to front end grip and braking compared to a Cayman. The grip issue on the NSX can be resolved with wider tires up front, but as soon as you put a decent BBK upfront then your front tire width becomes really limited because of the wheel offset narrow fender space.
I have driven the Cayman pretty hard and never felt front end understeer, on the other hand on my NSX after 10 laps or so I would feel the front end giving up in regards to grip and I had to resort to some interesting techniques to get the car to rotate properly.
A 2nd generation stock Cayman S can do 1:42's at Laguna Seca out of the box, that is pretty damn quick
compare that with a first generation 997 GT3 with R-compounds (MPSC) that do about 1:39 with stock suspension height/alignment
1st Generation Cayman's can suffer from Oil Starvation, Oil Ingestation when using R-compounds, Power Steering Issues as well (they don't have an electrical system like the NSX).
The 2nd generation are supposed to be better in regards to the Oil Starvation, and don't sufffer from the very famous RMS/IMS issues of the previous engine desgin.
The best place to gather information regarding the Cayman is over at
www.planet-9.com (formerly
www.caymanclub.net www.planetporsche.net)