GitHub in essence is still pretty much the same, there's products that have feature creep but I wouldn't say GitHub does that.
I can't say that I'm having issues with the performance either. I work with large PRs too (Especially if there's vendored dependencies) but I never ran into a show stopping performance issue that would make it "useless".
I can't say that I'm having issues with the performance either. I work with large PRs too (Especially if there's vendored dependencies) but I never ran into a show stopping performance issue that would make it "useless".