M-Tron came out just as I was getting less interested in Legos. I had the small recon ship with the magnet in the back, I forget the name of it, and that was it. I always liked the color schemes they had for it, though. Just so classic and timeless. I am very much hoping to find the Magnetizer (that's the big multi-wheel tank, isn't it?) and the larger ships sometime. I like that these themes are rather small, so collecting them all is quite possible!
M-Tron was awesome. I still have some of my old sets (they are boxed up and put away, but they are at least mostly intact). Amongst them is the Multi-Core-Magnetizer. That thing was awesome!