I'm not sure if this is just my computer acting up lately, but I went on the Automation Preview (had some fun) and I noticed that 3X speed makes the game 15fps slower. Those 15fps are kind of precious to me because my game usually runs 30fps. Also I noticed that I have the same fps (30) even when I make the game the lowest resolution, which usually gives me an easy 60fps.
Steps to Reproduce
Enable fps, measure fps when on 1X speed, 2X, and 3X.
This issue has not been confirmed by a developer yet.