Very stout, relatively simple
The thing is much heavier than I expected. Big aluminum extrusion base, beefy round clamp tube, plenty of steel hardware. It isn't the easiest to clamp to the roofrack crossbars (the front end), but it is very secure and gets easier after you've put it on and off a couple times. The clamp presses right onto the front brake (conventional road bike) - I'm not sure it would do well against an MTB V-brake (disc brakes are perfect).
Bought this because I had gotten the full Yakima rack with the Q-towers. Great buy and install was soooo easy! Just FYI you should order two locks separately when getting this because it will help securing your bike in case someone wants to permanently borrow your bike, if you know what I mean. LOL!