From what i know of, none of the custom roms support ART. You can only use Dalvik with them. From my understanding it has something to do with the rom files being DeOdex and not Odex like the stock rom. The rom developers like to DeOdex the rom files as that makes them easier to theme. I am not positive on this one but i am pretty sure that is the reason.
This rom says it supports ART, you could give it a go. A couple of weeks ago when i tried it it wasn't working though, but that was when it was first released, it may be fixed now. http://forum.xda-developers.com/show....php?t=2732110
im sure all the rom developers will get it to work sooner or later, it will just take time.
best of luck!