(WarpBuild founder here)
We have had a lot of users evaluate multiple tools including ubicloud but chose us. Typically, they've mentioned our runners being faster, our caching is very useful, and queueing delays being lower.
However, my last anecdata was from a few weeks ago. You can try us out and take a call for yourself.
Our focus is on CI runners and efficiency and I think that gives us an edge on the devex. Ubicloud is definitely cheaper though.
I think I skipped over evaluating ubicloud because they don't have macOS runners. There was another place I liked but I needed macOS runners they didn't have them either.
However, my last anecdata was from a few weeks ago. You can try us out and take a call for yourself.
Our focus is on CI runners and efficiency and I think that gives us an edge on the devex. Ubicloud is definitely cheaper though.