On a whim, I ordered one each of the clones of the PT2 and Mini for a comparison. I honestly cannot tell the difference to the real ones.
I mod them anyway, but these do not leak or offer an inferior vape. Since I vape a lot of different flavors (DIY) and am constantly changing during the day from one to the other, I ordered the multi-packs of each in different colors so I do not mix up my juice/tank combinations. In the past, I would always use an engraving tool to write a number on my devices. The color coding is a lot easier for my tired old eyes to keep track of.
In all my years of smoking, I never changed brands: I was a Red man all the way. Although I now have a few core flavors that never change, I am constantly trying new blends of DIY. Instead of paying 50 cents to a $1 or more per ml of juice, it costs me a fraction of that with DIY so I spend money on hardware. At least I tell myself how much money I am saving.
Fasttech is not the place to go to buy critical vaping supplies due to the long shipping delays. Through Malaysia one has to count on 30 days. However, if you are a tinker and want to try new stuff, it is the place to go.
Having said all that, you can get some really good deals on hardware in the US if you follow deals and steals, Vapor Joe's blog and use the Pennyvape comparison shopper.
Prices in the US are really starting to bounce all over the place. I can understand B&M's being more expensive, but it is hard to see how some internet retailers survive charging 50-100% more than the competition.
The only conclusion: it really pays to shop and to shop according to your needs. Although I hate to say this, ecigs are so much more work than analogs, but also more fun.