Did a course with
http://www.mountainbikeinstruction.co.uk/Did the course about 18 months ago, with a mate.
We had been riding for about a year and felt doing a course would bring our game on.
The course we did was the advanced one, and it was really quite good.
Rather than teaching us to suck eggs, the thing I got most out out of the day were tips to improve my riding, such as looking further ahead, standing off the bike to get a better balance, doing drop offs and tweaking my bad habits, to be good ones !!
We had picked up some biking tips, during our previous year, but having an intensive days training really brought our skills and confidence on.
The Athertons are also doing bike skills courses in Llandegla.