EDI has a common departure area; a better description of the lounge location would be "past security control".

Once through the x-rays, turn left and the PP/ServisAir lounge is located between gates 3&4. The BA flights won't be called from that lounge, and will likely be from gates 10 or 11, about 5 minutes walk.

It's perfectly adequate - hot toast in the morning is about the only distinguishing feature of it that I can think of. it never seems to get too busy either.