Wake Up Blow Job

This is something that I have never experienced. I have occasionally woken my wife with my lips and tongue on her pussy (she usually sleeps on her back) and dropped hints that it would be nice to be woken with a mouth on my cock. But so far it hasn't happened.
I have an occasional mistress who visits to service me every now and then, and sex with her is free adventurous, varied and fabulous When she is with me I enjoy her however wherever and whenever I like. Almost every time we sleep together i wake first and push my cock into her as a gentle wake up.for her which she loves. I've told her how much I'd enjoy it if she were to wake me once with her mouth on my cock . And she says she would like to do that for me. Unfortunately she's a lazy bitch in the morning and never wakes before me so it hasn't happened yet.
I shouldn't complain. I know how lucky I am to be enjoying so much sex, but I do.wonder what it's like to be woken in this way.
For guys who experience this, tell me what it's like? Is it worth waiting for? Should I find a girl who works night shifts and can do this for me after work ?