Dreamhost = used them in the past. I still have just a few names there.
No bulk management, so any DNS changes are going to be a pain. Renewal is very expensive, careful about that autorenew. Other than that had no issues with them. Edit: they used to have a 10 domains limit, unsure if that is still there or not.
Cloudflare = I'm not using it but people who are say there's not really support available, other than that they seem happy to.
Sav: Might have technical issues sometimes. Domains not transferring, etc. Overall I find them alright for what they are, a low cost registrar. I don't have expectations of 100%, perfect service.
Also they don't allow registration of dropped domains during the drop window. Support is slow but they tend to solve things.
The other one I don't know about.
Edit: I would use all 3 mentioned but I still hold my best names at Dynadot.