Mark was a great guide around the trails of Laguna Coast. I signed up for a half day of riding and he pointed me to the Path bike shop in Tustin to rent a bike. I got a great deal of $42 for a Giant XTC 29er for the day as long as it was returned by 5pm. The trails were a mix of singletrack and fire roads with some good climbing and rocky descents (not too technical).
Mark was really good company and we spent a good deal of the ride chatting. He knows the area really well and is able to find a route appropriate to your level. I'd have liked to have gone a bit further but was constrained by the bike store's opening times. All in all a great day out and would recommend to others.