welcome to the world of cheating tools, im sure you can sacrifice those 25.
ill just assume you're not a pilot or superhuman of any kind, so you should be ok with 40 FPS
By the way, max loss is around 5-10 FPS for me and im playing on a toaster, try and play around with GOS Performance settings
FPS in games does not have nothing to do about how much your eye can see.. Games are not just working well unless u got like +60fps and you will see the drop in teamfights (example from 100 to 80) u will notice huge amount of stuttering and slowness IN game. I wanna see you playing example CS with 30fps. Most games are not meant to be played low fps.