OS: Debian 8
GUI: XFCE
GPU: Radeon HD 5800 (drivers from repo.)
Fullscreen
No Steam Overlay

1) Alt key does nothing. (i.e. I can't ping.)
2) Minimal settings and low fps, ~40-50. (same with CS:GO). On windows with maximal settings, ~100+.
3) Noticeable input lag.
4) Region with lowest ping is US East with ~300. On my windows machine, it is ~60.

Please, for the love of my chinchilla, Dota 2 had better not be wrapped.