I have bought 4 pcs of Blimp from Fifthunit and all of them has workt ok.
edit: It´s not a K2 led.
I must say that I´ll dont understand how it can be so bright with only 3 AAA batteries. I have not done a runtime test but I have used one of them quite a lot and haven´t changed batteries yet.
It´s just as good as the Golston (but the clicky-switch is a little better on the Golston).
Even if I´ll mostly use RCR litium powered lights it´s god to have a really bright flashlight that runs on ordinary batteries.