No, there’s no chips – it’s a “pleasure” ride rather than a sportive style thing (I think, officially, almost 30,000 people ride it, so logistics would be mental!). I wouldn’t compare it to a sportive at all – last year, I cycled through Chipstead with 4 guys dressed as stormtroopers….
I don’t know about parking, but it’s not the best place to park on regular days – add in 10’s of thousands of people, and I imagine it’ll be terrible! Transport at both ends of the day is tricky – last year I stayed with friends the night before in Clapham & then cycled back out of Brighton to get picked up by the wife…this year I’m cycling from home to the start & from Brighton back home (should be my first 100+ mile ride!!)
It does get very busy – certainly at the bottom of any “hill” (I remember How Lane being particularly bad last year).