While I was playing a match of big team S&D on this version of Reachsky yesterday, I noticed that it ran...very, very badly, especially for an S&D map.
My FPS sometimes dipped as low as into the 60s even though fpsVR was telling me frametimes were well below 11.1ms for 90Hz.
None of the CSGO map ports have this issue, or even some Push maps that tend to be a challenge to run. Zombies are a different matter though...