First of all, the "aluminum" is so thin and fragile, that I managed to put a couple of dents in it just getting it out of the carton. When I first noticed them, I thought they must have been done at the factory -- until I managed to put a couple more in it while I was adjusting the hatch height, just from pressing down on the hatch at each end.
But the worst was this; The G4 Elite is designed to be installed on a truck that has no bedliner that covers either the rails or the tailgate. My 2008 Ranger has a factory bed liner (duh!). It doesn't cover the rails, but of course it covers the tailgate. Therefore, it is impossible to fit this tonneau so that the top aligns forward/back with the side rails. The best you can do is a quarter inch mismatch, because that's about how thick the bed liner is. The weather strip forces the hatch at least 1/4" higher than the rails no matter what you do. To top it all off, it leaked the first time I ran it through the car wash. But at least it does do the one thing I bought it for -- I can get into my bed from the front as well as the back.