A bit late with this reply. I do Hong Kong to Gulf of
Thailand trip twice a year (in May/June) and know many
delivery crew who do it much more than me.
Singapore to the Gulf of
Thailand is easy and passes some great cruising grounds.
Going north from Gulf of Thailand to just past Nga Trang is just
fishing net after
fishing net. You will get over most of them, but every 4th or so will hook up.
Record held by the boys is 18 hookups in one night. There is over 300 miles of this.
The
water off the bottom of Vietnam is shallow and gets really messy in strong SW Monsoon (now). If you stop at any of the islands, your
boat will probably be arrested and basically held to ransom by the local authorities. USD10,000 was the last fine I heard being extracted for stopping at Con Son (first hand account from someone who I have sailed over 15,000 miles with).
Ho Chi Mhin and Nga Trang can be entered if you have problems with the boat. But it's a costly business.
Hainan, despite having a magnificent marina and hosting
volvo race stopovers and
volvo race teams, Hainan still turns away yachts. Including dismasted ones requesting only
fuel.
If I was going from Singapore to Hong Kong at this time of the year it would be up the
east coast or the Malaysian Peninsula to Terreganu, across to Palawan, up to Coron and then straight to Hong Kong (if i didn't want to
cruise in the Philippines).
Or to Palawan via Borneo, but I find that trip a bit dull.
A straight shot from Terrenganu or Singapore to Hong Kong is possible if you can get good
weather info on the boat. Typhoons are a real problem and the only real defence is to turn and run back to Singapore. Some have run to KK. Disheartening, but probably a better experience than trying to hide in Vietnam, in bad
weather, hemorrhaging cash.
Once you get to Hong Kong, as pointed out earlier, the problem will be moorings. Difficult to find but not impossible.
For a short stay in Hong Kong - arrive August / September and leave October. For a longer stay, leave March / April. You will get 6 months for the boat before you have to start the Hong Kong licencing requirements (boat and skipper).