Not going to debate the popularity of SMOK products or why, but I honestly think their marketing folks could have done a much better job naming and helping users keep this mess of tanks and coil heads straight. It's enough to make anyone's head spin. By the time you find a tank you like, SMOK turns around and releases another one that also requires a different series of coils.
You have to be very careful purchasing coils. I've seen numerous websites that have the incorrect coils linked to the tanks, incorrect descriptions, and the like. Then when I KNOW I ordered the right product, the company ships me the wrong one. They are confused too, lol.
The SMOK baby series (not x-baby, lol) was where I gave up and STOPPED buying pre-built coils and tanks. I think SMOK contributed to this decision for me. It's much simpler to just buy an RTA and be able to put pretty much any coil in it yourself.
It's good to see threads like this though, especially with the compatibilty tables to pull all of this together for folks and have it as a reference.
I got rid of anything that didn't use the BBB coils, and even those are now in the vape closet. Too many coils to have to keep track of.