He could have a legit concern though, there is a problem in the game right now that it's not super good on very high end computers if the processor doesnt match the graphics card in speeds, mainly because there was no frame cap so it pushed out as many frames as possible.Well, I played this game with a low-end old fashion laptop and it was okey. You should check your setting though.
If they have a high end graphics card it could result in the game trying to push a thousand frames per second, and if the gpu cant keep up, well, the game gets slow. Anyway there is no real reason for the game to run at higher than 60, i have a 144 hz monitor but since no animation is higher than 60 it doesn't matter.
I gave some instructions earlier on how to force a profile in the game so that it has vsync, but in the next update it's all enabled by default as intended.
/A