I would have said Bartleby - it's the cheapest and the best at the same time, imo - the 14500 with the 510 is my sweet spot and I have 5V devices as well. The Bart stays at peak voltage for hours and it quite a different experience than the regular 510, mega and even the Tornado (which I like a lot) but since you mentioned it - the Protege, as far as tube style mods is a dream - still has the 14500/510. I can put cartomizers on it with no problem (well - add adapter that I keep on the cartomizer - I use blanks and have fitted 901 carts for mouthpieces - cartos can get rather hot in a peak 3.7v and above and the mouthpiece is a nice touch - thanks to Scottbee and others for the suggestion. )
The batt is cheap - charger comes with the full unit - 2 batts - although, the ones I got with the kit were unprotected and highly suggest (perhaps request from Steve, if you go this way) protected 14500 batts. I'm a heavy vapor and I get 8-10 hours out of the Protege and Bart. The thing I like about the Bart is that I can use the charging cable in the same way you use a PT so that when I disconnect I'm at fresh recharge and vaping a peak voltage for hours. The 14500 starts to drop off in the last hour but still is as good as a mega until it quits. The protege has a 5V PT (I have one for sale - cheap ;-) which will get better vapor from cartomizers but will also kill 510 attys because of the resulting wattage and kills flavors in the 510 as well, while the 3.7V will enhance the stronger flavors. My fav vape Habana Reserve tastes different on each device - great on the Bart and Protege, very good on the Tornado, weak on a Joye Stick V3 or 901? However, fruit flavors don't do as well at 3.7V - not all but some apple, berry, cherry, etc. and at 5Volts - fugettaboutit ;-) ...in my experience.
The batt is cheap - charger comes with the full unit - 2 batts - although, the ones I got with the kit were unprotected and highly suggest (perhaps request from Steve, if you go this way) protected 14500 batts. I'm a heavy vapor and I get 8-10 hours out of the Protege and Bart. The thing I like about the Bart is that I can use the charging cable in the same way you use a PT so that when I disconnect I'm at fresh recharge and vaping a peak voltage for hours. The 14500 starts to drop off in the last hour but still is as good as a mega until it quits. The protege has a 5V PT (I have one for sale - cheap ;-) which will get better vapor from cartomizers but will also kill 510 attys because of the resulting wattage and kills flavors in the 510 as well, while the 3.7V will enhance the stronger flavors. My fav vape Habana Reserve tastes different on each device - great on the Bart and Protege, very good on the Tornado, weak on a Joye Stick V3 or 901? However, fruit flavors don't do as well at 3.7V - not all but some apple, berry, cherry, etc. and at 5Volts - fugettaboutit ;-) ...in my experience.
