I think once you start getting into vaping more, youll find that anything lower than 1.5 Ohms is reaching the point of just plain ridiculous for a single coil. At .8 ohms, you would have to be using an awfully fat resistance wire, and not much of it... Two or three wraps of a big fat 26AWG wire is not enough heating surface, IMO to produce enough vapor.
There are a few arguments out there that suggest using low resistance allows you to run your battery closer to its native voltage for hotter heat levels, so it's better for the battery... Now, it IS true that you can get higher heat at lower voltage, I dont know if there is any truth to this being "better for the battery"... In fact I think it's a load of poop. Most of the new "big battery" voltage regulated mods have protection circuitry built in, which is also better for the battery...
So like I said, you will get more heat at lower voltages... But, with well built VV / VW mods out there like the ProVari (VV Only) you can put just about any coil you want on it, and its going to perform well... I can tell you this, at least IMO, a 1.8 ohm coil at anything over 5V is ridiculously hot, will destroy the coil, and destroy the flavor in your juice...
There is just no reason for anything lower than 1.5 Ohms... Again, just my opinion... Most of the folks that are wrapping really low resistance coils are most likely using mechanical mods with fixed voltage output of 3.7V. With 3V-6V variable voltage, you won't need to use LR coils to get significant heat production...