i have the choice of either getting a 2004 m6 or a 2006 crossfire 600... which is a better overall sled?

that depends on your riding I also live in MN and I ride a crossfir and I love it handling is great I am putting a 1 3/4 track under it but I like to find some deeper snow when possible and play in the ditch but the m sleds are fun to

i personally think the m series feel better when riding and the first year of production of the m 6 was in 05

The xfire is the same chassie as the 141 m. if you ride trails and only ride in MN get the xfire. if you only ride off trail get the m. I personally dont like my xfire in the very tight trails, its too damn long. but I love it for the bush beating/off trail I have been doing for the last few years in the UP. when cat makes a new chassie for the shorties ill get another shorty and put a paddle on it.