Crib top rail covers to prevent baby from biting the top of the crib

Yea or nay? I have seen ones you can buy and also ones that people make. I am considering it because we have a convertible crib that I'd like to last (also don't exactly want baby ingesting bits of crib). But I have also seen that covers can be easily taken off by baby and create an unsafe sleeping environment. Baby is 8 1/2 months old and just started pulling to stand.

Opinions?