I have run Knu alot. The kollisis or whatever is good stuff and it is real copper. The klmx is what your thinking of. Its thinner and cheaper its also a tinned alum. I use it for a ground. for a buck 50 or 75 its hard to beat for a 0 awg wire to run from front batts to rear batts for a ground. The other thing is this. Current doesn't travel thru wire it travels around the wire. So having a core that isn't a conductor is great. It allows for more current travel with less resistance. Problem is that it then heats up faster as well. Benifit of solid core is that it will allow for a longer period of current draw with out heating up as fast. drawback is that it also has a little bit of resistance. so yeah...