used my trasharoo for the first time today taking dogs to the beach (loaded it up with dog-drying towels). It was awesome to have al that extra space. I have the same tire size on the spare.
it isn't easy to install... I tried crossing the buckles through the spare tire holder, but that didn't work well.... so I just put the straps to the outsides of the holder.
I find the bottom more difficult to get my hands in, so I pre-set the length on the bottom, and make the top nice and loose... snap things together, and tighten on the top.
I am having some problems with my buckles, and sent an email in to the trasharoo guys.... I ended up taking a ratcheting strap and putting it around the circumference of the spare tire tread to make sure everything was going to hold. I've got an email in to the trasharoo guys to see what they recommend... I'll probably post up more about it after I speak with them.