It is on the expensive side, but then, with 10,000-ish less riders than RideLondon over the same length course and I'm guessing the same amount of set-up costs, it was probably to be expected that it would be dearer than RL. And of course, given that there are less riders, surely it should be less crowded on the roads than RL as well?
Having said that, I probably won't be entering - despite being about halfway between London and Birmingham, it's actually more of a pain for me to get to Brum than to the capital, so I'll give it a skip this year and think about 2018, assuming they run it again and reviews are good.