Well I went ahead and bought the Klein in spite of the top tube noise, got too good of a deal to pass up given it came loaded with 9 speed dura ace and sweet wheelset in very good condition. Turns out there is definitely something loose in the top tube I could hear sliding back and forth if you pick up the bike. My mechanic advised against removing the fork but put squirted some grease inside which stopped that movement. However, upon riding it there is still significant rattle coming out of the top tube when you hit rough pavement (almost all the time when traveling downhill speeds). Again, not sure if this is due to the loose piece(s) in the top tube or just normal noise from the brake cable rattling against the tube from the inside. Frankly I don't see how it is possible for the cable not to rattle against the tube unless you installed some sort of liner all the way through.