I did the unaffiliated one last year and its very similar to the PN just smaller it runs along the same course as pn. From what i remember there was no ditches last time but doesnt mean to say there wont be this time. Water etc was lovely to.
Hope that helps a bit i thought it was a nice course that rode really well!
It'll be my first event next year hopefully. A friend of mine did the unaff last year and said it was pretty straightforward and not very up to height. If so it should be a good first run, they may beef it up a little as its affiliated but the unaff one is run by the BE organisers so would imagine it's pretty similar
i did the unaffiliated earlier this year, thought it rode really nicely but there was a ditch which was full of water. Most horses didn't seem to bothered by it though as it was on the was back to the warm up !!