Make sure you get the right type. There seem to be two different models of RT30, one you can use as a tail pack/back pack, and one to use as panniers. I had a look at some in a local dealers and they hadn't realised, so I spent a while waving straps around trying to work out how it'd fit on, before realising. None seemed to have any instructions either.
Quality though seemed good, and the removable liner a bonus as I presume you'd be able to buy spares if either liner or outer wore out. Other bonus, as, long as you were in a safe enough place to leave the panniers on the bike (which you might want to given how hard it seems to work out how to attach them) you can just lift the inners out, to take with you.
Happiness has 125 cc