Hello boys and girls Looking for an upgrade to a 600 and I'm considering the usual suspects. Looking at spending up to $6k. The bike will be used for 99% commuting (350-400 k's per week). Are there any known problems with any of these bikes I should be wary of? ie gearbox or engine problems or anything equally horrid? Looking at ZX6R, YZF600, GSXR600, CBR600 etc.