I have not seen them, other than a random picture here and there.
Myself, I tend to stick with what lots of others are using. I just bought 4 more Efest 2500 mah 35 amp max batteries. I also have 2 Vamped 40 amp batteries, as well as 4 Samsung 30 amp protected cells, and a pair of Efest 50 amp 26650's.