Currently using the sigelei 30W with Panasonic NCR18650B batteries. They we're fine in my Evic but I was limited to a max of 11W. I have a sigelei 100W coming soon too. I was thinking of picking up Sony VTC4s. I've heard those and the VTC5s are excellent, although I know the VTC5s are hard to come by. Are there other options I should be considering? I imagine this topic has been covered, so post a link to a good thread or offer you thoughts here.