After buying two covers directly from the local Hot Springs dealer and seeing them last about 3-4 years before they start to take on water, we decided to purchase one online. We ended up buying one from Hot Tub Works. We also bought a cover lift. I loved the fact we could choose not only the cover color but also how it's built. We opted for a 4" (edge) to 6" (center) cover, folded 90 degrees from the original (that worked best for our setup) and upgraded the moisture barrier. The old cover was 3"-4" with a standard moisture barrier that acted like a sponge.
The last cover cost us about $500. This one was around $650 and that included the cover lift. It took about 6 weeks to be delivered to the door. We just put it on last night. It looks great but the radius at the corners is a bit large, hardly noticeable though. We took the figures Hot Tub Works had and used them. Length and width are perfect. It creates a vacuum!
Time will tell how long it holds up.