The entire ecig business is built on clones: copies of designs that someone forgot to patent. The benchmark ecig is an eGo - but 99.99% of 'eGos' are clones. The original design was by Janty, they had done many before that didn't take off, so maybe they though this one was a dud as well. Probably the biggest mistake ever in the ecig trade...
However the word clone mostly refers to APV copies, and mostly mechmods. So if someone says "I'll sell you a clone for $30" they probably mean a copy of a well-known mechmod design like a Nemesis that costs several hundred for an original.
From a strict viewpoint a clone is a copy that can be distinguished from the original without too much trouble, and a counterfeit is a copy that is hard or extremely difficult to tell from the original and sold as original.
As far as performance is concerned, most people seem to think that clone mechmods are about the same as the original. The quality is going to be different as one is $40 and the other is $220. The benefit of a clone is that it's cheaper and it's in stock. The disadvantage of an original is it's expensive and it may be out of stock. The disadvantage of a clone is that it probably isn't going to be the same quality of finish; and maybe instead of a voltage drop of 0.1 volts through the body of the device, it might be 0.2 volts. Maybe the original will last longer.
As the whole ecig world is built on clones, it's not something to get too excited about. If makers don't want to patent their designs and enforce their rights in court then it's up to them. It's just a business decision, and anything unprotected that is any good will be copied ad infinitum.
There is only one area where you need to avoid clones and that's
batteries. Any suggestion that the battery may not be by the original maker should make you walk away quickly - fake
batteries could be dangerous.
