I've managed to use my beverage lines for quite a long time too. However, I do use some extreme cleaning procedures to keep them contamination-free. A nice warm lye solution soak does an amazing job at ridding any sort of deposits in the tubing. Do recognize that using a lye solution is SUPER dangerous and requires protective equipment and care.
Maybe a pbw soak?
Let me tell you the other reason I’m not keen on bringing new vinyl tubing into my brewery. Vinyl does contain volatile compounds that take a while to leach from the tubing. I try to help that process by pre-boiling new tubing to help get the compounds out. Keeping ‘well-seasoned’ and relatively volatile-free tubing in my system makes sense to me.