I would/did loose the liner & got a bed mat after talking to the salesman at the canopy dealership.(talk to the guys at the dealerships in your area to be sure)I was told I would not get a good solid footing with a liner that can move around under the canopy.(makes sense to me)
Look at the lots where canopies are sold & you will see a pile of liners in the back somewhere.They're there for a good reason.
I went with an aluminum vs fiberglass for cost savings & weight savings.I don't remember the brand,but here it is on my Colorado.
I saved a few hundred bucks by going with the aluminum & I save gas with the weight savings also.
As you can see they are making them smooth sided now so they match the truck a lot better.
I did have a Fiberglass LEER on my Silverado & loved it,it matched the contours of the truck so well it almost looked like a Suburban.
Either way,FG or ALU,a truck is neckid without a canopy IMO.
And remember to check the clamps regularly.:thumbup: