Just to add my 2p..... This is an extremely worthwhile activity for ALL concerned.
It enables both groups to "see the other side of the fence". Indeed apart from the immediate knowledge gains at the time, most participants go on to spread that knowledge through both the pilot and ATC community. A Good Thing
So, please come on down to the Costa del Swanwick, you will learn something to your advantage and you might even enjoy yourself!
Rgds BEX