Ahh I usually fly with them (approx once a month) . They depart usually 6:30am from the big lounge and 8:30am on Saturdays. When you get to the airport, they are the first check in desk on the very far left of the terminal building.
I, personally, wouldn't waste your cash on private lounge. I've gone in them before, and can't say it was value for money. There are a couple of coffee shops and drinking outlets when you go upstairs, just before you go thru to departures, and then loads more when you do.