I have honed for others a few years now, and must confess that it is probably my favorite part of this hobby these days.

As stated above though, my rather sizable collection gets lesser use than desired as a result of that.
I do try to shave test a bunch of those I get in for honing at one go though, so at least 3-4 times a week I will do most of my shaves with my own herd.
Shaving the head with a straight also adds to the total real-estate that needs shaving, it helps a lot.
Well, less and less every day if I'm to be completely honest about it