At risk of jacking the thread...
While I can say 45mg seems terribly high to me, I've long wondered about how much nicotine a person is actually absorbing when they vape.
I gave up my 1/2 to 1 1/2 pack a day cigarette habit in October 2013 and started with 16 - 18mg. I still use 18mg in coffee flavors in the morning, but stepped down to 12mg for my afternoon/evening flavors. I still go to a 15-18 mg nic content juice to tame the monster if I'm having a real craving.
I don't really notice a nic buzz, nausea, or headache except in two circumstances:
1) I chain vape for an extended period
2) I use my 510 bridgeless atty to test a dozen flavors in one sitting (which I have done on multiple occasions - I just get so excited when I get vapemail!)
I've read that studies have been inconclusive on the absorption rate and that estimates range from 10% - 40% absorption rate and that full-flavor cigarettes deliver about 1.4mg per stick (absorbed). So, even if the absorption rate of nicotine from vaping is 40% and I'm using 12mg juice, I'd be getting the equivalent of 4.8mg per mL consumed, or <4 smokes...if absorption is 10%, I'd be getting the equivalent of 1.2mg per mL, or <1 smoke. I normally have a 'rotation' of flavors I use during the day and don't exactly keep track of how much I use in a day, but it can range 1.5-6 mL, probably averaging around 2.5 - 3 mL
The questions that have been bouncing around in the back of my head is "should I step down to 6" and "does it even matter as long as it's not making me sick and I'm not having cravings that drive me back to analogs" and, frankly "would the flavors come out better if the juice didn't have nicotine in it'?
btw - I'm a cigar smoker also. I've always enjoyed them, but really picked it up as a hobby during a previous 7-year break from cigarettes. Although I haven't had a cigar since right after I started vaping, I've got a humidor full that I'll either use or they'll be a nice, well-aged treasure for someone after I pass (hopefully still decades away). I've been tempted to break one out just to see if the nic affects me. I'm not sure how much of a test that would be, since cigars have never affected me the same as cigarettes.
Not necessarily expecting answers...just musing...