Originally Posted by oakleydo
I ride XC. I'm in Kansas, so I don't need to worry about mountains
I have signed up for a couple of races in Oklahoma and Kansas, for fun rather than glory. I already have the 3700 (bought last summer). Would I be better off upgrading it?
What is it that you don't like about the 3700, or are you just looking for something new?
I have seen a lot of people complaining about the components which come on the 4500, and $500-600 will get you a lot of new components to replace the pieces you don't like. You can get a pretty nice fork, bottom bracket, wheels, tires, disc brakes and upgrade the derailleurs for that price and get exactly what you want.
The 3700-4500 are all alpha aluminum frames and have the same geometry. The only advantage would be the quality of manufacture for the frame (my 4300 was made in Taiwan) which may or may not be an issue. My wife's 3700 is comparable in build quality to my 4300. Very nice welding jobs on all joints on both bikes.
I personally would upgrade the 3700, but like I said, I'm still relatively new to trail riding too. I also have a tendency to buy mid grade things and upgrade them as time goes on.
I would do this:
Tires to Panaracer Fire XC 2.1" - $35
Fork to Marzocchi MX Comp w/ETA - $239
Avid ball bearing disk brake (front and rear) - $140
Shimano LX hubs (or similar) $15 front + $30 rear
Wheels to WTB Dual Duty XC Rim - $80
Total $539
Figure in shipping and installation of everything if you're not up to it yourself or have a friend who can help out and you're probably looking at around the $600 MSRP for the 4500, but you'll have a lot more bike where I have found it really counts.
Like I said, I as a relative newbie would probably do the above, but I'm sure others will have more input.