I've flown from Denham, Booker and White Waltham for one reason or another. Each has strengths and weaknesses, but overall, they're all pretty good - I doubt that you will make a bad choice from those three.
On the other hand, the people talking here about microlights only as a transit route to flying light aeroplanes are missing the point. There are many good reasons to fly microlights, and thousands of pilots get years of enjoyable recreation out of microlight flying without feeling the need to fly light aeroplanes. Personally, I fly both, but would not be upset to be constrained to microlights if I only flew for fun. Microlights have been flown around the world by hardier souls than me, but most keen microlight pilots have done a fair number of multi-hundred mile trips very enjoyably.
G