Can't comment on thunder run,as I haven't seen it Stu, but definitely tough, especially at the start. I ran 38 minute laps last year, but will be taking it steady this year, looking at just under an hour a lap, and try and keep it steady.
Wetter,thanks ,maybe do a few laps together if you fancy. Last year I wore Adidas Kanadia trail shoes to start, and they were fine, but the course was quite dry, the last two laps I wore road shoes for a bit more cushioning . It's grass to start, and you go straight up a hill for about a mile , then it levels off ,through some woods and down hill to half way, then a short climb into some more woods, and then on to a private road where you can see the start/ finish, then you drop down ,come back on yourself for few hundred metres on grass then quite flat to finish the lap. My Garmin said it wasn't quite 10k. Perfect for a sprint finish.