I like Circuit Days events, but to be fair they're all pretty good.
The problem with the circuit day events is they cost twice as much as the Javelin or trackday.co.uk events despite having the same open pit lane format. Plus at the circuit days ive found theres always guys running full slicks in cars which are essentially competitive track ready carswhich make it a nightmare IMO as their closing speeds through the tight stuff is savage so your permenantly watching your mirror for guys trying to overtake you on a bend
Plus my last circuit day event at Rockingham the guy asked me how i thought the event was, but got really anti with me when i said the morning session was great but the afternoon was rubbish because the track layout was too short and had to many cars on it so ill probably not bother with them again, unles theres a particular event on a certain day i want to do