No problems with the frame at all. No dents I don't think, though I can check closer later today. Paint's a bit dull, and some scuffs. It has many many miles on it. Been a super-reliable year-round bike for me for the last 6/7 years. Commuted on it (most of my commute is on trails), raced it (even won on it), rode it rigid and as a HT - and it was great in every application. Love the geometry - always felt perfectly balanced and comfortable. Steel rides so nice on singletrack. It was a tiny bit small for me, but I think it would probably fit you perfect as I'm closer to 6'2" than 6'1".

I'm getting more into racing, so I got a 2010 Niner One9 used off ebay. Lefty fork, I9 wheels. Fast bike. The geo is a bit more aggressive than the KM, but I'm used to it now and love it for racing. Would LOVE an Air9 Carbon, but I already have a carbon (Specialized) geared HT. Plus I have two little kids, so my wife would kill me if I spent that much on a bike. I'm pretty new to Niner, but very happy so far.

Here's some pics of the KM: