I skimmed through this thread and I guess my first question would be. If the item was defected why didn't you return it to your place of purchase? Being online or at a local shop? Dealers I've dealt with have satisfaction or return for refund. So, why didn't you just return it?
1. The OP did say that he did contact his retailer (see his initial post) but did not hear back.
2. I don't know what dealers you are dealing with, but I have never come across a dealer that gives satisfaction guarantees in this business, especially on tanks, clearos and coil heads, or anything else that is heated or is designed to touch your mouth. All these things are usually only 24-48 hour DOA warranties and I have seen many that state no warranty at all, which means satisfaction has no bearing on anything. I have come across retailers online who say they offer satisfaction guarantees, but they also usually have high restocking fees, prices about 3 times higher than the plethora of discount retailers most of us buy from, and I have no idea if they actually honor any guarantees anyhow. Talk/type is cheap

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None of the local B&M vape shops in my area would ever let a customer return a tank for any reason. Heck, not even batteries. and they charge hefty prices for the most part. Not sayin' it's right or wrong, just sayin'. Hell, my local B&Ms wont even let you touch the product (like a mod or APV) before you buy it. No joke.
They are responsible for replacing a defective product within a reasonable amount of time. That is the cost of doing business.
If you knew what volume most small business retailers (not just vape) have to sell just to break even, and if you tried it yourself, you'd change your mind in a heartbeat.
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At any rate, as far as I'm concerned, there are a few things we can learn from this thread and all the problems we have seen in the last month or 2 alone with QC from e-cig MFGs in China...
1. Don't expect QC to get any better. It's obvious not a big priority.
2. Don't buy anything unless it has been on the market for at least 2 months and buy only from high volume retailers in order to increase your chances that you are buying the latest and "fixed' versions of whatever fad product is out.
3. Don't expect Chinese vape MFGs to honor any warranties. They simply are not interested most of the time, it takes a lot of time, and it isn't worth it for them, especially since they know you love their stuff anyway, they know you are hooked, and they know you will buy the next big product they release, even if you tell them you will never buy their brand again.
4. (something not evident from this thread but something you all should know) To increase your chances of getting service from a MFG, never buy any e-cig product from anyone unless know for a fact they buy their stock directly from the manufacturer (aka authorized reseller). If you buy your stuff from a retailer that buys their stock from a wholesale distributor (a middleman) and if you buy from a marketplace like Amazon or eBay, MFGs will not honor any warranties. This is a fact and you can email all the major MFGs out there and they will confirm this (send them an email and pretend you are a potential retailer looking to buy wholesale from them). They claim this is because they can't know for sure that you have a clone or not, but it's merely another obstacle they create so they decrease the amount of warranties they have to service. So be careful who and where you buy from if you are the type who demands service after the sale. Your best bet is to find a US based (for those of us in the US) retailer who charges high markups and warranties their own sales. I don't know of any, but I'm sure there are some out there. Remember, service and warranties come at a premium. You can't expect to buy a subtank mini for $39 or less and get service too. It just ain't happening. If you want action and service, that tank would have to be marked up to at least $65-75 to justify service and warranty claims as most warranty claims are bogus anyway. But they still waste time which is money.
5. Learning to enjoy a vape at lower temps might also cure a lot of problems. Not sayin', just sayin.
Not griping about any of this, just stating some facts for y'all. The underlying theme in this industry tends to be "buy and use at your own risk". Just remember that when next week's new sub-sub-sub-ohm tank or 100000000000 Megawatt mini mod is released.