No, you won't get taxed for $600, but you're taking a huge risk buying an item like that from Hong Kong. Sure, it might be cheaper than getting one here. If you're lucky, you'll get what you pay for (a cheap and nasty product that will probably break). If you're unlucky you'll get a cheap knock off that is badged up as a good brand. Being cheap does not mean you are getting a bargain.
Seriously, save your money and buy one from a B&M shop. If you buy one from HK, you risk it not arriving, then the seller assuring you they'll send another, then keep stringing you along until the time has passed to get a refund. Then you never hear from it again and you lose your money. If it arrives broken, or stops working quickly, you'll have to send it back to the seller using tracked postage, which to that location is pretty pricey. A seller is supposed to pay return postage, but getting it out of the Chinese is impossible.
If you go ahead with this purchase, I'll look out for you when you come back to ask about getting a refund.
