For those seeking fine and high end tailoring, here is some information. There are tailors and then there are the elite tailors. Sam's tailor and Raja fashions receive mixed reviews when doing Google searches.
Do keep in mind that the most important cost factor in a suit or any other garment is the fabric. A high end fabric like Zegna will make the cost much higher, but the quality and longevity will be much better. In the end, you get what you pay for. WW Chan at 94 Nathan Road has Shanghai style tailoring, but you may have to make an appointment a month out, and then the turn around time is 6-7 days. This is the best high end tailor in Hong Kong.
http://www.wwchan.com/
My personal recommendation is Lord's Tailors at 30-32Connaught Road 9F/
http://lords.hk/contactus.html
Lord's are also Shanghai tailors and have high end fabric such as Loro Piana and Zegna. Their prices will be about a third lower than WW Chan. Lord's is on Esquire magazine's Hong Kong recommendation list and have been in business for more than 30 years. The Conrad(and Mandarin Oriental) concierges send their customers there.
At Lord's, I bought a made to measure summer suit made of Zegna light tropical wool. I had three fittings and the order time took 4-5 days. They have their own factory with 50 people working with both a day and night shift. I am very pleased with the Zegna fabric suit I bought. There is quite a bit of hand stitching on the suit, such as the lining and button holes. The suit was not inexpensive, but it is a good value given that the same suit would likely cost double or triple in the United States. In the end, you have to pay for a high quality suit or garment, but it is better to have one excellent suit than 3 or 4 of average quality.