Originally Posted by
NightShift
Right on.
If the OP was asking about replacing a '70s or '80s aluminum frame I would say yes, definitely, but even then it would be less about the inherent fatigue characteristics of aluminum and more about the improvements in alloys and manufacturing processes.
I would recommend riding one of GT's classic steel triple triangle frames before buying the Trek. There's certainly nothing wrong with a steel Trek, but I've always preferred the feel of the GTs. And they look cool. I occasionally see them turn up dirt cheap on Craigslist, but rarely in my size.
I never see any steel GTs mine is '01 and it is a triple triangle frame. That feature is one reason I think may help my bike last some time. Whenever I get another bike it will be new, since I've already done the used craigslist way with the bike I currently own.