Firecat came out in 03 and the M came out in 05. If you are going to look at things this way for Cat, look at it the same for Polaris. The Wedge was close to 10 years(I think), then came the gen 2, evolved and edge. IMO, and I have owned a gen 2 and currently own 2 edges', those 3 are basically the same and that lasted from 94-03/04(again, I think). Let’s not forget the Year of the Fusion, which ended up being a short year before the IQ came out. All in all from a general, non-technical point of view, every manufacture has a great redesign and then tweaks it for years. If you get into the details, then you could almost argue that all manufactures have new sleds every other year.