I’ve got about twenty domains listed with them. No problems after 2-3 years, but I do wonder whether it’s a good idea to use the same vendor for DNS and domain registration.
Normally a registrar isn't going to have top tier DNS infra so you may as well separate, yes. Exceptions might be CF/Google/AWS/DO, but personally I don't like to use the big guns as registrars in any case. I use Namesilo and never had any issues but on the other hand have never run into any of these sorts of issues either..
