I’ve been running Calyx OS on my 4a for around a couple years now. It was a bit of an adjustment at first but now I don’t really miss much of anything. I rarely need to use anything from the Aurora store, just mainly FOSS apps as there is a replacement for just about every Google app you could think of. The only thing I have come to miss lately is not being able to use Android Auto, since I just got a car that has that functionality. But that is a slight complaint.
I have never used it so I can’t say, though I haven’t heard any talk of it not working, do with that what you will.