Since a friend introduced me to e-cigs and I decided to make the switch, I've done some shopping around at various manufacturer sites for the e-cig products with the intent to sell them locally, and I can tell you that one angle TW is using versus some of the more "discount-oriented" sites is the option of personalization. It allows you to re-brand the model and call it whatever you want... such as the Titan. The discount sites simply
buy the kits and market them under whatever product name is provided by the manufacturer.
There are quantity requirements for this service, however, and it puts the retailer in the position of making a decision... quick sales and lower profits, or slow sales and higher profits. The answer to the decision lies in how much capital a business has to start with, and how soon they need to see returns on their investment. Low capital = quick product turnover, High capital = more turnover time allowed.
Also, product personalization is a time-tested marketing strategy. Folks in retail use the term "value added", for example, to describe things like personalization, extended warranties, etc. Personalization, as a "value added service" from a distributor/manufacturer, creates the perception in the customer's mind that this is a unique product to that retailer, and sets it apart from other products that may well be similar, if not identical in construction.
As far as knock-off clones, that's actually a misconception from what I've been able to learn about the e-cig manufacturers, with only a few exceptions. There are several companies in China who (I'm guessing on this part) either share the patents collectively due to a joint research venture, or have non-exclusive license rights on the patents. They ALL manufacture the same products, and they're all quite close in proximity, considering the size of China itself, and the fact that about 70% of them are all in the same province. Most likely, they're all in the same industrial park. Now, I'll grant you that the quality can, may, and likely WILL vary from manufacturer to manufacturer, but... well... you get the rest of my point, I'm sure.