The PetStep ramp is the best quality pet ramp I was able to find after much research.  I had even brought one ramp home, and then returned it because it was poorly designed and constructed.  It was the same price as the PetStep.  The PetStep model has a rubberized texture on the ramp, which is fantastic.  All other models I found had a gritty sandpaper for traction.  This was hard on human hands when manuevering the ramp, as well as the pads on the dogs' feet.  The dogs are not the delicate type (3 of them, each 100+ lbs).  The ramp is very sturdy which helps the dogs feel secure when using the ramp.  No wavy wobbling even for our hefty pups!  And... Amazon's order processing is great.  The ramp was delivered very quickly.