jp1, RPM pretty much covered all the bases.
As for performance, the magazine road tests put the 6 spd. at just about 1/2 a second faster than the automatics in the 1/4 mile. (If that's important to ya). Of course that all depends on how good the driver of the stick shift is.
For the convertible top, as with any roadster, the more it goes up and down, the quicker it will eventually wear out. But the Crossfire seems to come with a sturdy fabric that may hold up better than some lesser vehicles. I suppose only time will tell.
For what you get (a Mercedes in disguise) there really is nothing else out there that even comes close.
Drive one, and let that make up your mind.
By the way, there is a beautiful roadster for sale in the forum section right now. Good Luck.