I would put product quality and customer service on the same level for criteria. There are companies out there that if you get a battery that underperforms, they'll change it out for you - most of the time completely free. As far as the type of equipment, it depends what you want. "Cigarette" style batteries don't last as long as the bigger eGo style batteries, but are discrete and have that "cigarette" feel, if that's what you're looking for. Smokeless Image, Bloog, Halo or V4L all have good reviews in this category. You also can go with the eGo style batteries from a variety of vendors, like Hoosiers, SI, Madvapes, Good Prophets (and the list can go on) which have a longer battery life (so you might only carry one or two eGo style batteries compared to two or three of the smaller ones), but are larger (like a small cigar). It depends on what you want, but I would always suggest looking up customer service for those vendors and weighing it with the product quality.
	
		
			
		
		
	
			
			 
				
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		