I play on my deck for testing all the time and it runs wells. It is possible that some cutscenes dip but with some deck settings tweaks it should run great. Unfortunately we have to wait for Valve to give an official deck compatibility rating.

I’m buying it - any performance tweaks you recommend?

thank you! I would play with the scaling/half rate shading stuff, I can try to get my exact config when i have some downtime, but it should work pretty well out of the box