My opinion on this matter is this:
if the original item has no patent/trademark on it, then it's fine if someone cloned it. If the original patent has a design patent that only protects the look and appearance, then the clone must have some difference in appearance so that people would not confuse it with the original, otherwise it will infringe on the design patent. If the original item has an utility patent that protects the FUNCTION of the item, such as working principle, or an non-obvious improved design that offers unexpected benefits, then anyone that make a similar device would be infringing the patent, and such action should be strictly forbidden as it goes against everything an innovative, capitalistic nation like America stands for.
Luckily, most e cig devices are not very patentable from an utility perspective because they all use the same basic principle, that's why you see so many clones. I can't just change the shape or position or material of a coil post and patent my "new" atty because it's too obvious. In this case, I can't stop anyone from cloning my design. If, however, I discovered that by changing the atty chamber shape to a specific shape, I somehow improved vapor strength or volume by 1000%, for example, then this would be completely unexpected and non-obvious and I would expect to get paid for my R&D (patent it), and if someone want to clone my thing you can bet I would sue their .... off.
