I moved about half my domains (I have about roughly 30) to Cloudflare and then stopped as I started hitting caveats. For instance they considered some of my domains “premium” and wouldn’t take them. I was having problems using them with some hosted website providers, etc
I let the rest of my domains transfer to SquareSpace and it’s been mostly painless (besides Google Domains completely fucking up my email but that’s wasn’t SquareSpaces fault). I’ll probably run out the registration on all of them and make a decision on where I’m moving my domains next year. Probably won’t be Cloudflare though.
That said, Cloudflare definitely seems cheaper than SquareSpace.