My 1st matthews bow wasn't the top/best they offered at the time, which left me wanting a better bow or the latest/greatest.
So when I was ready for a new bow I bought Matthews' latest and greatest, which was the Drenalin, a great bow, still a great bow, which is 5 years old now? and their newest bows don't leave me wanting one really, I honestly could hunt forever with this bow and never need another bow IMO.
I'm sure I'll own another matthews one day, in no way does one need the latest bow each season.. plus I'd rather know my bow for 5 years or so vs. having to learn a new bow every year.
I assume say the Helim is better than my Drenalin, but by how much? I haven't really heard of any major break throughs since my bow, so is the helim 5% better? it's not like the bow shoots twice as fast, twice as quiet, half the weight etc...
If/when there is a major break through I'll probably want a new bow, for honestly I could easily see using my current bow for another 5-10years.
I'd be more likely to buy a new quiver/accessories for my bow than a new bow at his point.
I like my setup for the most part, great bow, great arrows, great release, great sight.
So essentially I'd get the latest and greatest when I need something new, if not I'd save my money for something I need. Once you have a great setup why change it when the benefit is very little.
Also my local bowshop will honestly tell me if there is any difference from a bow to another..., they'll straight up say your 2003 bow is almost no different from the new 2004/2005 bow... down the road they may say oh this has improved...in 2010... so sure you can get a new bow and it'll be better, but not much... or, oh the game has changed, this new model blows everything out of the water.
Having an honest pro who's been around the block to tell you straight up what's going on, is quite a nice luxury IMO. Especially when they're not getting rich off their lil business and they know you have the cash to buy a new bow and they still tell you don't bother...