Can anyone provide insight into the difference b/w the Miyata 610 and the 1000? I've poked around a bit at past posts and saw some limited discussion. I also looked at the Miyata brochures--I see the tubing is slightly different. Are the chainstay lengths the same (and are there any other geometric differences?)? Can anyone who's ridden these bikes offer insight into the qualatative differences--i.e. is the 1000 all it's cracked up to be?