I agree Cal the Runthrough races are great I've done a few of their Wimbledon common halfs and the support at Ealing is second only to VLM in my experience. But this is a mass participation race bang through the middle of London on closed roads and it's never going to cost 20 quid. No one is forced to do it so why moan? I got in this year and probably will cough up, it was my first half a few years ago and for various sentimental reasons I'd like to do it again. I'm a slow plodder and big flashy races like these are sometimes fun to do too and yes hopefully I will pb which in my case is sneaking under 2 hours. And they do at least give you a really nice tech teeshirt which would cost 20-30 quid to buy.
It's a lovely race, well organised, lovely route, great local support. I've done it twice and plan to do it next year. And the entry fee is pretty reasonable compared to most of the other local HMs going on around the same time. Even I can afford it