my work colleague did it last week in cardiff, they rented a cottage for the weekend and made a go of it, he said it was amazing, not to difficult either because they did it as a group they waited till everyone was at each obstacle to progress. with that the time wasn't amazing and could hvae been a lot quicker but for fun and that they was in a large group he said it was amazing.
i was looking at doing the North london one this year but it fell on same weekend as North vs South and that was the end of that idea haha.
gonna do it next year, might do the same thing and just stay at a hotel the night before and do one half way up the country