Once you get it setup and working, it won’t cause you any issues. The reason I called it “spotty” is because I have noticed some instances where a new MX record won’t show up at all, even after multiple days. It is entirely possible that that bug has been fixed.
Personally, I would recommend that you use Cloudflare for additional protection and stuff instead. It’s totally up to you what nameservers you use though since you have a custom domain.
Because of the way the system is setup, you have to set epizy.com nameservers in order to connect your domain to your hosting account. So its just easier and a lot less confusing if we just say “use our nameservers” instead of “Set our nameservers to add your domain to your account, then its up to you if you want to change them back somewhere else again. But if you change them to something else, you need to set the appropriate A records.”