I had one and was goin down the highway and my bikes fell off the back and got run over by an 18 wheeler. i got my bikes totaled and had to pay for the damage on the 18 wheeler and i didnt have insurance on any of them. i was a little but drunk but my advice to you is just toss them in the bed of ur truck dont bess with any gadgets like that youll regret it and prolly get rear ended and ur bikes will get smashed up just some advice from experiece good luck with ur purchase.
My second hand knowledge is that they feel shakey and cheap, but seem to work alright as long as you secure them properly. All of my second hand knowledge comes from the sportbike world though, so they are only carrying a single bike but in the 400-500 lbs range..
^^^ that guys a herb and doesnt know what hes talking about dont mind his stupidity he sucks at life sorry. im smarter listen to me..i fucked his duaghter in her tight little anus