Interesting thread. I just bought a GT+ but am waiting for the bags before I take it from the dealer. Can't ride now because of weather so who cares.
Anyways, I've had a few GSXRs ('02, '05, and '06) and they were all rattly/noisy. My last one, the 2006 GSX-R1000, was noisy from day one until I sold it a few years ago. Never had an issue with it. Unfortunately, this kid I sold it to was hit by a tractor trailer on it so that bike is no more which broke my heart. The kid only had minor injuries which was very lucky.
I wanted this bike because I loved the K5/K6 gixxers. This thing should be a comfy K5.