I had Cerec and Voco Grandio.

I was “muscle tested” for bio-compatibility on over 50 different dental products. Officially its called “Applied Kinesiology” ask your dentist if they use people like that for compatibility testing. Mine cost £50 ($100) and I got a second opinion at the same price…..it cheap, it works, and even if you don’t understand it, its better than guessing/hoping a product might be ok.

If you are in UK, I can recommend a couple.

"All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third it is accepted as being self-evident."

Sunshine