I live in the Milwaukee, WI area and have a 10 year old Master Spas hot tub. I replaced the cover after 5 years because it was waterlogged and sagged a lot. The more it rained or snowed, the more the weight would build up and the more it would sag. The sag was most noticeable not in the middle (hinge area) of the cover, but between the hinge and the outer edges. IOW, there were 2 sag areas, one on each half of the cover.
After replacing the cover with another Master Spas cover, the new cover started to sag after less than 1 year. I realize now the MS cover is probably not as good as many aftermarket replacement covers.
Question to you: Have you had a sag problem (sagging cover that is...)? If so, was it the original OEM cover or aftermarket replacement cover, or both? What solution would you recommend?
Thanks for your input!