^ What juice would that be?
It seems the type of juice has a lot to do with how long a cart lasts, how dry you can vape them alond with vapor production and a myriad other things. It seems the juice can have more to do with the quality of the vape than the device used to vape!
Oh and I notice you're in Canada, so any advice on getting juice through customs or your experience with ordering whichever juice you use that vapes dry on your mega carts would be appreciated!
There is no magic secret wrt the juice, just the consistency/viscosity of the liquid. Although I roll my own, with a PG/VG base of 80/20, I kept with the intended viscosity of the original liquids. Whe adding VG, it needs to be cut 4/1 with distilled water. Some folks think this is diluting their VG, it is not. It merely allows it to flow better. FWIW I vape a 5-6V with standard carts, without burning either the filler or the atty. I vape 3-5ml/day.
High sugary content flavours or highly coloured flavouring does affect the wickabilaty of our liquids, especially in "cartos", not to mention fouling attys quicker.
I vape Dekang for my commercially bought liquids (RY4, 555, DK TAB, Cuban Cigar and French Pipe). What I have seen from many vendors is that their liquids are too viscous. They may be good for dripping, but that would be about it. Not to fault the vendors here, because many perfer dripping. I use the HighPing mod for my carts. It works extremely well and gives me a near dripping experience.
I haven't purchased liquid from abroad in a long time. Whe I did, I played poker and bought 16 x 30ml in one shot. 16 is what I believe to be a limit for box size to go through without raising suspiscions. I guess my tip would be to order juice and equipment separate. Should it get held up at Customs, you can defend if the package only contains parts, but you are SOL should it contain liquid.
... and yes, a 3.7V device is a 3.7V device and they all vape the same. The rest is just hype AFAIC.