

No major issues found
Some light audio crackling
Would not recommend. FPS drops too much; unplayable.
Extreme slowness / fps drop. Unplayable
Too slow to evaluate the game. Unplayable.
Runs like native in the hour I played.

Tested 2 campaign maps and endless mode. All good. Downloading scenarios does not work: tachyon.exe (downloader?) crashes, which then makes the game unresponsive.
When I used PROTON_USE_WINED3D11=1, the game at least loads up the main menu, but then freezes when trying to start a game. I can't be bothered to test other workarounds, because the devs of the game are lazy cunts.

Tower models or textures do not show, and FPS is horrendous. But it is playable (the towers shoot, they're just invisible). If you set the GFX quality settings to lowest in game, the tower models will show up, but they're entirely black and untextured.

Small FPS difference against Windows, specially when you face a big number of ennemy. But except that the game run fine.