I usually haven’t, but I installed Clam about a month ago on my desktop, ran a full and complete scan, then left it running scheduled scans. Hasn’t found anything, and I get a lot of software from outside of my package manager, and use wine for a lot of it, so I’d say my risk/exposure is higher than most.
I think it’s fine to go without AV on a linux desktop, but I like the peace of mind. There will definitely be more things targeting linux sytems as/if more market share is acquired, but in terms of security it’s more important that you harden the system than run an AV.