Cedarjet,

If you're transiting through HKG, you can simply stop in at the consulate and get your visa in about an hour or two. You'll need cash, probably RNB (my memory fails me), they don't accept credit cards/cheques. You might be able to do this in SIN also, but I don't know. I've never investigated the SIN option.

Why are you getting your visa in SIN? I have used a service in NYC with just a few days turnaround. Have you compared prices to getting it in NYC? It's been a while since I went through the HKG consulate, but that was by far the fastest and easiest way to get a 6 month or one year visa.

Have fun on your trip,
Bubba