I'm currently using Cloudflare for DNS. It works fine. I know there's also Hurricane Electric as a decent reputation free one.
example.com and subdomain.example.com are hosted with different hosting providers.
Is it possible (and advisory) to not use a "separate" DNS server, but have the domain point to example.com nameservers, while setting up A (and other relevant records) for subdomain.example.com with example.com hosting server (shared/reseller hosting is used)?
Would that work (much/any) worse (in terms of DNS resolution) for subdomain.example.com, compared to having it hosted as a subdomain with example.com account, on the same server?