About going from 15 to 40 I can totally relate. Been gaming on my laptop for past few years and have finally decided to buy a new rig. ~25->120FPS in Fortnite. I wasn't really enjoying it at 25FPS, but I'm living quite far away from friends so I used it to hangout. I wouldn't play otherwise, it's frustrating when everybody else is twice as good just because of FPS.