You lot will have an excellent time. Its a bit off-putting but rather funny too, trying to hold a conversation in the conference room. Everytime a plane takes off everyone looks around insync then it goes, conversation resumes for a bit then another goes up, heads turn etc etc..........
The views from up there are great too, defo take some kind of camera.
Also bear in mind if you are going by car that there are not really any public car parking spaces at the foot of the tower. You have to use the Terminal
2 car park so take a lot of spare change with you for the machine as its pretty expensive as car parks go. Have fun.