For most of the guys from USA or other countries, when you visit hk or china, how long do you go for ?

I want to go HK, Macau and Shenzhen however I'm not sure if 1 week will do ? I am from NYC.

A week to do all three can be done, but its at a stretch.  From Hong Kong, bothe Macau and Shenzhen are about an hours travel away by jetfoil and train respectively

depends on how much vacation time and/or money you have, if you speak Cantonese/Mandarin, what your purpose of the trip is, and if you've been there before.

Never been to HK or China, well I'm trying to go to HK for the party scene and see if I can pick up some chicks at LKF, shoppng and then try some visit some landmarks and try out some wg / ktv.. Macau for the gambling and w/g, shenzhen for shopping and w/g.

A week will only give you jetlag twice in a row.  I've done a week before and it's not fun at all, the initial landing in HK was fine but when I came back a week later, I found myself sleeping 3 days to figure out how to get my body back to normal.  Since we are both from NYC, I can tell you that in March, there will be deals for under 1000 for a week in HK including hotel and airfare.  You do what you want to do on ur own if you want, but I think even some tours are included.

my advice would be to select one location and make the most of that in the week.
all 3 would really require 1 month i reckon.

It's definitely doable to visit all three places within one day.  In HK alone, you can easily spend a week.  If you are just there for the mongering and nothing else, one wk should be enough.  Basically, land in HK airport, spend 2 days in HK while going to local 141s.  Then, take a ferry over to Macau: try a few saunas (lot more expensive than mainland).  If you gamble you could spend 2 days in Macau (otherwise one day should be enough).  Go to Zhuhai for some cheaper Mongering actions.  Take a bus to ShenZhen.  There you can try a handful of WGs.  And, cross the channel to go back to Hk.

Best to not try and see too many places. If you're intent on HK, stay there a few days, then go to Macau for a couple. If time permits, work you way to one more destination.

I have to say that I have been in HK, Shenzhen and Macau all in the same day (they really aren't far apart).   I have gone day tripping to Shenzhen to go electronics shopping, come back at the end of the afternoon, dropped off stuff at my hotel in HK, and then wandered down to Shun Tak to go to Macau.

Macau can easily be "done" as a pure normal tourist in a couple of days.   It's damn small, you could walk from the ferry terminal to Lisboa in about 20-30 minutes (directly).  We aren't talking a huge, huge place here.

HK takes longer, I have been many times and there are still new things to see.  

Shenzhen, well... the doorway to the largest country on the planet.  It could take forever to get it right.

I would suggest if you have the time and the cash that you plan at least 10 days or more.  You might want to try arriving on a Thursday, and plan to stay through 2 weekends, which gives you the prime party time twice.  You may want to sign up for a bus tour of HK to see some of the sites in a sort of organized fashion.  

For mongering, well, it's pretty much like shooting fish in a barrel, except that the fish are strapped to the end of the gun so you can't really miss.  From massage the walkups to HG to saunas to KTVs, there are about 101 ways you can have fun, alone or with friends. and all of the are good.  Some of the worst reports here are still better experiences than you would get in the US or Canada.  It's a blast, but bring plenty of money, because once you start, you will want to keep going

I am from ny. 1 week just don't cut it considering the time it takes to get there.  I say minimum of 3-4 weeks plus. If just HK, you can slide by 2 wks.

if it is just hk, then 2 weeks is all you need.

if china, one whole month at least!!!!!

china is a big country, you can spend a year there and barely scratch the surface

only if i have the freedom to spend so many weeks there lol.

for the bros living in hk, you guys are living the life!

One week is not doable at all and it's not even worth it to fly all the way to that part of the world for one week. I guess if you really want to just breeze through everything you can even inlude Japan, taiwan, korea, russia etc on your itinerary as well. HK needs about 5 days to see everything at least. Macau looking at 3 days and Shenzhen 4 days  at least. I mean you're not just going for the mongering right? If you are , might as well stay in NYC and save that $1000 in airfare and monger there. If you're going to be going to HK for the scenary, shopping, foods nightlife etc and mongering on the side then HK, Macau, shenzhen is the most awesome time you can have but make room for at least 2 weeks. The first time I was in HK, I spent two weeks there as well and got to experience everything HK has to offer.

but in terms of then scratching the mongering activities of china, u only need 2 months u reckon?

how do you get this deal?
i was looking to go to HK in March from nyc (before my trip got canceled due to work) and found the airfare to be around 900 usd not including hotel.
each night in a hotel would've cost around 100 usd.