I just bought a Supernova E3 single, I am happy with it. Not as bright as some of my battery power LED lights but no batteries. I have a pile of dead LiIon battery packs, it's a small toxic waste dump. The Supernova should be upgradeable to newer Cree emitters as things progress. The E3 has a matching taillight, both headlamp and tailight stay lit for ~5mins after stopping.