One of the great things to buy in Hong Kong, is musical instruments. It is mainly because they're…read moreso cheap, being both manufactured in the area and tax-free. And if you're going to buy a musical instrument in Hong Kong, quite frankly, the best place to go is the Tom Lee Music store.
This place is a huge hypermarket of all things musical. They have musical instruments, all sorts of electronic recording equipment, tickets for local concerts, and a very good sheet music department. I am amazed that in the same stall, I can buy a a Korg piano, a saxophone reed, The Best of Blue sheet music for flute, and a microphone. It really is a one stop shop all musicians.
There are a number of branches in Hong Kong including Wan Chai and Causeway Bay, but the TST site is by far the biggest. If you're want to try musical instruments, it's probably best to go to the TST store, because they carry more stock.
They often have very good discounts and sales on. I recently bought an electronic piano for half price, simply because it was a slightly older model. They also offer free delivery, and in some cases (like setting up the piano stand and stool) free installation if required.
I would be interested to see if they have the same brutal returns policy as most Hong Kong stores, however I'm unable to, as every item I have ever bought in Tom Lee, has been of the highest quality, and has not failed me. This includes the flute that I bought from the TST store in 1988.
Definitely give it a go, especially if you are a visiting tourist, looking to take some instruments home. You will probably not buy cheaper back home.