355 quest: GTS or Spider?

I have been a Ferrari lover for many years, and am finally at a point where it would not change my situation financially to go ahead and buy one. I'm planning to replace my M3 Convertible. I've always loved the 355, so that's what I'm planning to get. I figure it will save me $70,000 over a used 360.

So...I want an open-air car. Which is the better 355: the GTS or the Spider? Is the Spider as stiff as a GTS or Coupe? Does the Spider flex and rattle, etc? Is the convertible top prone to breaking, leaking, etc? Which seems to be holding its value better?

I'd appreciate your opinions. I don't have the chance to drive both cars, so I have to trust input from others.