Hello, and welcome to the forum.
In answer to your question, I know of no inherent problem with the 90's clear coat. As you may be aware, some water spotting is impossible to get out with all but the most aggressive wet sanding, and even then you might still see some residual marks. In some cases it must be re-sprayed, but hopefully you do not have it that bad.
A picture of the areas would go a long way in helping to determine what is going on.
|