I have seen some light wall fail but not that many but i doubt that they will still be in service after 30 years like many of out heavy wall liners. I always say that light wall will work fine but if asked i will always recommend heavy wall.We install a few dozen light wall insulated liners every year and then go back and clean them. I never see any damage or signs of wearing out. I clean some that are 15 years old and get heavy use, no issues at all. Know no problems with them, combined with the lifetime warranty, lower cost for the customer, I don't have a problem with it.
That is really surprising I know some guys that are always trying to be the lowest price and they typically never insulate but i am surprised not one out of 10 recommended it. Especially since just about every good liner manufacturer recommends itStrange that I called at least 10 different installers over the last few days and none of the them recommended insulating the liner