So I received my vamo v5 in the mail today and i love it. However it is quite long in the 18650 battery mode but i love how the battery has like a 2000 mah lasting ability. But it is just to long to fit in a pocket so im thinking of going down to the aw imr 18350 800 mah battery and i see them on ebay for 2 for like 12 dollars. madvapes is all sold out. And the shipping is free. for this ebay listing. My question is how long will this battery last I am like a medium to sometimes heavy vaper at times i had to carry a spare evod battery with 650mah around with me when i was useing those would I need to do that with these too? Help please Cause if i do i need to look into buying a battery case as well.