Gnus are made by Sp Fastec, you can find all the info on them here
and their latest models, Videos are here
. I have the new 2011 Brotherhood and dam they are great, the extra ratchet alows for those tweaks when you need them.
Having said that I also use K2 CTX, Not sure why everyone says too many moving parts. I have not had an issue and yes they move when you put them on and they move when you take them off, but after that they are totally secure, more so than the Fastecs, As for weight, sorry I am not doing 360's and so forth but I have never felt the weight and it has never stopped me carving hard and fast amongst the trees.