Derek M.wrote a review of Rhino-Rack Universal Side Loader on December 30, 2014
Familiarity: I've used it once or twice and have initial impressions
The loading system works really well and the loader is well built. However, it is designed to only be used with bare bars. The bars must have no attachments, not even kayak pads or SUP pads. The videos online demonstrate someone using them but note all videos show a car rack with absolutely nothing on the bars. Therefore this would be good of a strongly built recreational kayak but nothing higher end that would need attachments or at the very least pads.