As it stands now, unless Congress stops the regs, it will put the e-cig business out of business. Only those devices available in 2007, or earlier, will be allowed to be marketed. And those weren't very good. Or, the newer devices will have to be tested to meet FDA approval. The test is expected to cost a minimum of $1,000,000 per device. Most companies offer more than one device. This also applies to the liquid that is used. This is what will really hurt the mom and pop businesses that mix their own liquids. What's really silly is if the business makes a liquid that contains 2.4% nicotine, and the same liquid with different per-centages of nicotine, each will have to be tested, no matter it's the same liquid, with the only difference being nicotine content. Then there's the matter of the tanks, cartomizers, atomizers that hold the liquid. They will have to be tested as well. There's some debate on whether batteries will have to be tested, as these same type batteries are used in cell phones, cameras, and other consumer goods. A consortium of, I think, eight of the largest manufacturers of devices have filed, or are getting ready to file, a lawsuit against these regs. As it stands, only the big cigarette companies will have the money for the tests, and each only offers one or two devices that are sub-par compared to what else is on the market.
You can find more info and opinion here: https://www.e-cigarette-forum.com/forum/threads/fda-deeming-regulation-proposals.556080/