My parents in their 80's had bathfitter installed in 2000. They were happy with it until 2015 when they had the problem of water between the liner and tub.
The company has been out several times since then but the problem keeps coming back. Now the lady is telling them that there is no more warranty and that they will have to pay. They are happy to do that but the problem keeps coming back.
The tub and enclosure still looks to be in good shape but is the product at the end of its life. They are seniors and I am afraid that they will lose their balance in the tub.