I too lean on the heavy side when wicking with rayon, in that other thread using too much rayon was described as giving a wet t-shirt taste for a short while, goes away after it settles and breaks in. That's how I gauge if I used enough, if I get the t-shirt taste it's going to be a good build.
Yup Sally's is the way to go, I've been using it for a few years, given a bunch away and still have 3/4 of a box, it's a real bargain.
With the juice I use, on my builds and the way I vape, my coils gunk in three days. I just rebuild every 2-3 days, I don't want to vape the nasty stuff that comes off gunked coils.