I use the official ones for both, but haven't even considered looking for others.
Jaeger is a little annoying in that what configuration the library accepts depends on the language. For example, you have to modify your code to emit B3 (zipkin-compatible) traces, which is annoying. Leads to PRs like this: https://github.com/grafana/grafana/pull/17009
For prometheus, I was using the official Go client, but I found the victoria metrics one to be a lot simpler and lighter. My go.mod was a lot smaller after swapping.