On the average, once a week or every two weeks, usually multiple hours. Occasionally, when opportunity presents itself, a sleepover or an out-of-town trip.
Slowed down a bit the last few months due to a health issue. When I first started in 08 on average I had about 3-4 sessions a week. Last year I was down to 3-4 a month. At the moment it's more like 2-3 times a month. I find I go through insatiable times when I just can't get enough. The only thing holding me back sometimes is budget. I just love fucking hot young SPs who know how to bring it.