Ive been to Munstead- the course are absolutely tiny- so go if you want a tiny course-BUT the XC is very twisty and a few very trappy fences into dark with funny light, the course did not flow well at all.Ground is very hard too.
Mount Ballen is nice the course is up to height but straightforward. Nice galloping course.
The dressage is on the all weather and the SJ in the main arena which they water. The ground XC is flat and even (I don't think it is ever grazed) and they do a lot of ground prep although it can still be firm. I would say a good first PN.