everything is coverd in this and the other tread. just one thing to add:
vaping with 100% VG is also hassle free on a REO. on a ego batt with an atty or carto they are cloged up quite rapidly, also the liquid change colour into something brownish that tasts yuck. had a max 2 day life span on the clearo's, with atty's i could extend it with blowing out and flush a bit of fresh liquid and a lot of waterboiling sessions and vodka. now we can do somewhere between 1 and 2 months with an atty with all day use, then a waterboiling session and it's good to go again, and again and again...only for this the reo will earn his money back in no time, with the way less spilling liquid and the huge extension of atty-life. haven't used carto's on the reo but i suspect it will have the same result.