I've been to HK twice using travelers checks lately. Even in a city so world class as Hong Kong some banks will take them some wont! Its all about location. If youre in a residential area like Wong Tai Sin or Lam Tin its hit or miss. But go to area with business people, tourists like Central, Jordan, Tsim Shi Tsai and you should not have any problems. Still not all bank will take them not matter how high class or modern the area is. One Bank of China will accept it and another wont. Its not uniform as banks in the states or Canada.
Some banks will limit your max transaction a day and its a small limit so you might have to make a Pain in the ass trips if you spend a lot. Plus you have to pay the same fee all the time! I suggest you just take cash to Hong Kong too much trouble looking for a place thats accept them.
And bank lines in Hong Kong are long compared to here, but still no where no near painful as banking in China where its so SLOWWWWW! Its like everyone has to tell their life story to a teller there. I once spent 45-1 hour in a Shenzhen trying to cash traverlers checks during 3pm busy time. Damm!!