Dynadot, because it allows domain tasting. If you impulsively buy a domain you later regret, they'll buy it back. Reminds me of a blog post I wrote on why we buy bad domain names: https://medium.com/@jasoncomely/why-i-buy-bad-domain-names-e...
I got a ton of domains as well, but it's largely having a positive effect on me. Once I have the domain for a project I'm working on, I always end up at least shipping a MVP, as otherwise I feel like I'm spending money on something I'm not using. If I didn't get the domain, I'd probably end up releasing nothing, instead of something. Some projects survives longer than that.