Oh yeah, that one. It was one of the two alternative options I considered before finally settling on the H502d, but the lower per-cell efficiency, higher price, inability to easily clip it to a pocket, and the need for battery matching in cannibalistic usage scenarios, all tipped the scales towards ZL. Since I don't really need the highest brightness settings on either light and don't plan on getting secondary 14500s, the Spark had no redeeming points left for me. They say its NW LED tint/bin is really well chosen, though. (And it's 115˚, isn't it? )