From my understanding (full disclosure I have not tried these like I said, but I have researched them a bit) the standard 50/50 set up will work with 100% pg or 100% vg but it might not wick it in as well and the 100% pg may be a little more prone to leaking out... but if you use a drip shield that is not a big deal.
Waiting until they are back in stock will save you 3 bucks per unit... but you will have to wait until they are back in stock and I have no idea how long that takes, I was not willing to wait around and see if they came back in just to save 6 bucks on the 2 units i ordered. Honestly 1.5 vs. 2.0 ohm is probably not going to be a HUGE difference in your vape experience, the 1.5 will be a bit hotter, probably warm up a touch faster and will use a little more juice. 2.0 is probably not a bad place to start since the coil is probably going to hold up a little more to the abuse of a new dripper. Really the flavor differences are more of nuances when you start playing with different resistances in the same design of atty, not huge earth shattering differences by any means (at least by the atties I have tried different resistances with). The biggest difference you are going to notice is that you will have to turn up a 2.0 more than a 1.5 to get the same vapor.
