I can't compare the lounges, but one option you also might consider is the Continental Presidential Plus World Mastercard. For $375 per year, you get a President's Club membership, plus Elite access at airports, complimentary Hyatt Gold membership and certain other perks. Available only for US residents. It could be a good value if you don't have elite status with Co and may be flying regularly with the airline. Check the t&c carefully, though.