I've only owned the ADCO cover CW sells. It's the brown/tan one with the tyvek (white) top. They call it the "Designer" series. Here's a link.
ADCO coverAs it is the only one I've owned, going on three years in the AZ sun, I can't comment on whether it is better or worse than other brands. I will say, however, that the quality is not the best. It was shipped with some buckles missing and one zipper no longer works. It has kept the RV clean and protected from the sun and I would buy another.
But, the one I bought is sized for an RV 23' to 26'. Mine is 24' so I have 2 feet of very heavy material that is gathered up at one end. It doesn't look as neat and tidy at the nice pictures you see on the web site. It's actually pretty frumpy.
Maybe next time I'll but the next smaller one and see if I can get it to fit. I'll return it if not.
Good Luck,
Eric