A good dealer will let you drive a C2 and C4S back to back for an extended period of time so you can get a good feel for how both cars handle. More than likely because both cars feel really different it will be easy for you to decide which you prefer. A good dealer will also let you come back and do it all again just so you can confirm in your own mind which way to spend your money. Whichever you prefer you can probably find a used one at a really good price, provided you're not looking for a very particular or unusual spec. Then if you like the 997 you can wait out the full price and glitchy first year and sell you used car without taking too much of a loss.