faster seems to have no difference in meaning from speed, which is handily beating it in number of questions and (in my opinion) sounds much better as a tag.
I created the running-time tag a few years ago, but it looks like speed has overtaken it.
While I think running-time is more precise, I'm not really hung up on which is the 'main' tag.
Faster should definitely be synonymed to one of them.
3 years ago
2 years ago