The two sets of spacers that come with the K-Drives are both for the rear bolts - thin ones with the sissybar, or thick ones without it. Use the ones you need and put the others someplace safe. Because of my bike having a towbar mounted to the same bolts I had to have the thick ones machined down to half width to make it all work (something I couldn't do with easy brackets, despite international phone calls and emails to the guy who makes 'em, who made helpful noises but produced nothing).
I've had my K-Drives for over a year - love em. As was mentioned the brackets are more obvious than the easy brackets with the bags off, but they're still not ugly. Besides, I rarely have my bags off, so I don't care.
I'd prefer to have the more secure mount between the bags & brackets, without having to modify things with extra plates etc for strength.
If I could have one thing changed with my bags, it'd be the addition of quick release snaps below the straps so I don't have to muck about with buckles every time I open the bags.
