I just had my tub/surround replaced by a real, old-fashioned local plumber. He used a real tub, Americast, and swanstone surrond: (It's 1/4 corian. solid as a rock).
I love it.
I priced 3 liner companies and they came out either very close in price or alot more. I was stunned.
The sales pitch is astounding, and all 3 told me how bad the other 2 were. I decided to believe all 3 of them and get a regular replacement and I'm glad I did.
My plumber makes alot of money tearing out the cheap liners. They bubble and crack and leak. Don't do it.
The only drawback is that it does take 3 days to replace with real materials. But there's no guarantee that a liner company will actually do it in one day, anyway.
Think of it this way: By the time you discover they can't do it in one day, what are you going to do about it? They've already torn apart your old tub and it's unusable. So, are you going to take them to court?
Skip the liners and get a real americast tub and swanstone surround.