It really isn't annoying, at least not to me. If you count off 15 full seconds, or better watch the sweep of a second hand, it is a long time. When you are using a flashlight you end up panning around on a lot of objects. You should be able to read this paragraph twice in 15 seconds.
The blink-blink is pretty quick too, and you barely notice it after a while. In fact, I think the worst part about it is that you get too used to it, and probably would not notice if you were using primaries and needed to change out at the blink.
Night-Ops has their batteries for sale now, by the way: 1600 mAh, $35 for 12 in the Blackhawk catalog. Anyone tried them?
Scott