I diid this course at Bogod last November. (I also have a 570QE). I really enjoyed it, there were only two other ladies there so we got lots of individual attention. Mind you, I didn't have so far to travel. The other ladies were staying overnight somewhere in London to take in some of the sights to justify the cost I think.
You do learn a lot about your machine - I'd had mine for a few months and not used it much before I went. I came home with a booklet full of samples, having had a lovely time with other like minded sewing people which is always a joy.