I'd say Huang shouldn't worry about that. I doubt his volume is high enough to hit a watchlist, especially when it's just one or two items per package coming across as a drop-shipment to individual customers. It's harder to get noticed when it's a drop-shipment like that.
It's LARGE shipments like the ones I run on regular orders that get the most notice.
Still, even if Huang continues to mis-declare the item, he's not the importer - you are. If you get questioned and don't want to take a risk, just tell the officer you don't know why the exporter would have declared the item at that value, but the actual value is [insert real dollar value] and that you don't mind paying the taxes.
Honestly, the taxes AREN'T that much in relation to the hassle you'll have to deal with if you get busted. Huang's products are SO competitively priced, that I'd outright call you a cheapass if you wanted to lie through your teeth to save the $6 GST on the $100 item you bought from Huang.
As another scare: if you fail to produce actual believable proof of the paid value of the item, customs has the right to reclassify and redeclare the value, and have the power to tax you based on the MSRP of the real deal (if they believe it could be the real item). For example, if you were trying to import Huang's replica blast belt, and they don't believe it costed you $15 (that's what was declared on my shipment), they could very well charge you taxes on the full value of the item (CP site is currently down, so I can't get an MSRP.) If they really want, they could hit you with the penalties as well, but how hard they hit you is also determined by how willing you were to co-operate in the beginning and how hard they want to try and prove a point.