I did this last year, as a training run, prior to an April marathon. I was there for work and had a 22 miler scheduled, so did this instead.
I cannot say enough good things about this race. The crowd support is amazing pretty much all the way, the organisation was smooth and the course is a PB course. I am hoping to race it this year, if I can sort work over there again. There were water and energy bottles every 5km, sponges every 5km and various video recordings taken around the course, plus at least 5 live bands and a couple of spin classes alongside the route.
Living in hope, I officially started my 18 week schedule tonight