This is a headlamp that has been produced under many different brand names(all exactly the same). I actually have the River Rock version.
This headlamp has been scrutinized for the lack of proper heatsinking and plastic housing. Several people have reported a melting of the housing so I beefed up the heatsink and would recommend you do the same if you purchase it!
Also, the optic used makes a pretty tight beam that many have reported they do not like, so diffusing material of some sort should also be on your list. I find it to be more useful when diffused.
In reference to your K2 concerns, I believe all of these headlamps use the older K2's (Mine Does) so you should not have any problem.