Good advice Brewman.
My tub is on bromine, my water level is below the headrests, I leave the cover open 30 mins while shocking with MPS, so that's what confuses me.
They are not completely shot, but are showing some wear, so i put the extra set in the garage until the old ones are really bad.
It was very nice of Sundance to comp them, but considering my long running battle with the worst Jacuzzi dealer in the world, they have done a great job of making things better over the last few months and also appreciate the recent 2 tubs I referred for jacuzzi.
I must say, Sundance customer service in California is very helpful and seems to genuinely care about their customers.