Priority Bicycles really is a great source for best bikes I've had. I have the 600ADX, the newer 600X...the one with suspension fork. Really great bike. I also have a Surly Disc Trucker and it's tough switching back to it. Pinion gearbox took me a bit of time to adjust at least letting up pedaling when want to shift especially if in a critical timing situation like mis shift on a steep hill then re-shifting. Learning curve. I'm not sure about the rear hub of Priority 600, the pawls on the 600ADX are louder but also very tough. Also something I have tuned out. Also bought their Priority Current (bike model name) Ebike...another great bike. Excellent customer service and response...24/7. I feel the ebike frame needs stretched out a bit from saddle nose to handlebar though. I'm 68" 275 lbs and the saddle adjusted back all the way still is 1" forward of pedal axis. I'm in the medium frame...Large frame would have possibly fit better. But as for 600ADX, I'm in a small frame and fits really well. I know 600 and 600ADX are different at least by the fork, but as a bike for touring I can recommend the 600ADX especially if riding off road surfaces like C&O towpath. Smooth ride.