From what I have heard in HK, Costa Allegra is not a good ship to aboard.
Someone said that the ship has lost its power for many times.
Also, you will be surrounded by numbers of Chinese passangers
(with unacceptable behaviors!!!!!!!!!)
If your schedule is flexible, I will suggust you to aboard the Costa Classica or Legend of the Seas.
Or you can consider to begin your cruise in Singapore,
the SuperStar Virgo (sister ship of NCL Spirit) is really outstanding.
It will only take you a few hours flight from Hong Kong and the ticket is really cheap (Recently I saw the offer: Singapore Airline, HKD$2000 including tax; fuel subcharge etc.)
Super Star Leo 08/04/00;Star Pisces 08/12/01;
Omar II 2002; Star Pisces 06/08/04; Omar III 09/17/05;
Golden Princess 01/15/06; Star Pisces 07/09/06; SuperStar Aquarius 3D2N 07/06/07;
SuperStar Libra 3D2N 01/16/08; Rhapsody OTS 6D5N 02/08/08;
SuperStar Virgo 4D3N 05/18/08