For the record, the Qantas first class lounge was able to store two pieces of hand luggage while my wife and I left the airport for a couple of hours. They stowed it in the closet behind the desk, although the agent made quite clear that they were making an exception for us.

BTW that lounge certainly lived up to the hype. I would have paid good money for the meal we had there. Excellent staff and facilities, although the wifi was a bit pokey.