I have mixed experiences of airport lounges. When I went to Canada and the Rockies in 2013 we were due to fly BA and there was no airport lounge in that terminal (I forget which) but then the flight was changed to Air Canada from a different terminal and the group was able to use a lounge which was good because we could meet at least some of the others (we sat round tables which rather restricted our movements). However, when I went to Canada and New England last year with BA we flew from a terminal with a lounge and it was pretty dreadful - the staff on the door were most unpleasant because I was on my own and hadn't met up with the rest of the group before going in, which apparently messed up their seating plans, and once inside it really wasn't worth the money and I never saw anyone else in the group.
These are the only two holidays I've been on where an airport lounge was included and, like daveJB, I'd rather have the choice. Personally I prefer to wander round the terminal, look at what is on offer food-wise and then find somewhere to eat and/or sit and people-watch until it is time to go to the departure area where I can more easily look out for JY labels and make contact with others in the group.
Ann