Someone suggested I try Supermaven yesterday, it's got some good benefits over competitors. It has a 300,000 token context length so it can send a very large amount of context for your completions, and it has an extremely fast API response time (usually less than 200ms) so completions appear near-instantly as you're typing.
It's the first "copilot-like" tool I've used, and I've only been using it for a day, but so far I'm liking it. And I've already signed up for the $10/month pro plan.