When using aftermarket panels and cover CAPA certified is your best bet outside of OE. Fit and finish are usually good but the material quality on some bumpers is lacking eg I did a MB 600 front cover, the OE was a mix of plastics including polyurethane, the aftermarket one had none in the mix meaning it will probably crack instead of tearing.
Unless you run into something like this chances are the CAPA will be similar in materials.
On the other side of that coin is some car like some of the Japanese models they really pinch pennies where it cant be seen, the covers are horrible crap, they crack and split easily. the CAPA is a better cover at less than half the price. GM covers seem to be reasonably durable.