I have had the Xtang series on my last 4 trucks. very nice, and for the money you can't beat them. I have had the one that snaps with the buttons and the other which is more of a tongue and groove fit, which I prefer because it is easier to put back on when it is cold out. I hardly ever use the bed of my truck, or in a manner in which I needed to remove them. It is more of a cosmetic addition for me.
I have bought them all at www.autoanything.com
and all have come with free shipping.