Baditudes got this covered, but I just wanted to chime in with my experiences. Go big. I got the 900mah VV Spinner after fiddling around with "cig-a-likes" of all sorts (disposables, kits, etc) with a vivi nova tank (and a mini), and it was a universal difference. Battery life, tank life, ease of use, incredible flavor and vapor output, customization, etc. Absolute day and night. Go for the big guns and get yourself a 900 or 1300mah ego style battery. Only tank ive tried so far is Vivi nova but i swear by them. As long as you're using the right 'style' device (as opposed to cigalikes, just my opinion here) than you'll notice the improvement and have a new habbit.