The ADCO cover we are using on our 38' 5Ver fits very well, and has held up great.....considering it is now 13 years old....now, it was used first year on our 2009, then we stored it away....until we put it on the first year with our 2019.....it was always big on our 34-ft 5ver (which is why we stored it), but fits very nicely on current trailer - doesn't flap to much in the wind. It also has alot of straps to keep it snug and zippers so that we can still get inside or open storage doors.
We protect the gutter spouts and King antenna to avoid tears.
IMO, the key is to have a good fit.
I hope this helps.
Mike