I'm sure it's a very good course, but are you sure you wouldn't be better off just getting out into the countryside fairly regularly and going for walks, and building up your fitness and experience that way? It's cheaper and requires a lot less organisation!
The sort of things you want to try to cover, in no particular order...
Basic navigation - map and compass.
Basic navigation - GPS (if you have one).
Suitable Equipment/Clothing choice.
Moving over different types of terrain.
Route Selection (distance, terrain, bail out options if weather turns etc.).
For what it is worth I have done two courses with PYB and as other people have said - worth every penny.
I have heard nothing but excellent reviews from PYB courses. You won't go wrong with them or any of the other national mountain centres. (e.g. Glenmore Lodge) I plan to do my summer ml training course at PYB. If you are serious about improving your skills/knowledge then don't hesitate and get a course booked. Good luck and enjoy.
In reply to Mountain Spirit: Am I right in thinking that the reason you want to do this course is because you want to be able to keep up when you go out with a group, and because you don't want to waste too much time on longer walk-ins?
Although I'm sure the PyB courses are great for learning navigation, preparation and planning, I'm not sure they'll be much help for just covering ground faster - they definitely won't be a magic bullet that'll make you twice as fast. It sounds like you basically just need fitness and experience, not a weekend of someone showing you what a ring contour looks like that.
Just to add to my original reply. I've put my money where my mouth is and booked onto my Summer ML training course at Plas Y Brenin. Glenmore Lodge was also considered but Snowdonia is nearer to me so it was the distance that swung it in the end. From what I've heard though, they are both superb centres and well worth the money.