I went in March. I thoroughly enjoyed the half-day.
I was very sheepish about stumping up the £150 for an hour and a half of tests, but that said, the interview by the Guild members afterwards was worth the £150 without the tests?????
The Guild members were extremely helpful and very approachable types.
My verdict - do it! I will be spending tons of money as a result, but hey - you only live once and life has no rehearsal.
It could save you a stack of money in the long run - or boost your confidence if you get the result you're looking for.
Either way - best of luck Buddy!