I'm not going this time, but you absolutely have to get as soon as they open. When I went in November, they let us play with the 737 and A320 sims. Take the first tour when you arrive and try and get onto the simulators at the beginning of the day, otherwise the queues were a few hours long (thus leaving you less time to do the more constructive research). I had already flown a circuit at Gatwick in a 737 classic and landed an 800 at Geneva before the 10:30 presentation.
There is plenty of time in the afternoon to ask your questions and visit all of the workshops. Make sure you understand exactly how the CTC wings cadet scheme works before you go down and prepare your questions first. Although I monopolised his time, I talked to the director of the wings program at length and this is crucial in allowing you to make an informed decision. Don't be afraid to ask tough questions as you will look foolish later down the line if you don't know what your getting yourself into.