Road Cycling - Advice please -- resuscitate or replace?

i'm getting back into cycling after a several year hiatus. i took my early-90's aluminum frame trek in for a tuneup and new tires. turns out that the cassette teeth and chainrings are worn, along with some other issues. bottom line is that it will take about $400 to do all the shop is recommending.

i realize that $400 would go a long way towards a new one, so i kind of hate to put that investment into the old bike. on the other hand, i know the current bike is a good fit (although i do like the higher stems i see on some of the new bikes), and i kind of hate to "dispose" of it. i realize that a lot of the technology has improved and that bikes are now lighter -- my original plan was tune up the old, get in shape, and maybe consider a new one.

obviously i'm conflicted. opinions?

thanks!

$400.00 seems like a lot of cash for a new drive (is this for a total rebuild?). I'd take it to a different LBS. A cassette, chain, bb, and chainrings should no be more that $100.00 unless you are upgrading to 9 speed. I hope you can change tires yourself?

I ride a new Allez Elite and an 87' Aluminum Cannondale. The two pound weight difference is not really noticeable.

I'm on the same shoes TM3. I took my bike to a LBS, the tune up lists for 50 bucks. I was very specific on the things that I noticed were wrong. The guy said they may have to change the chain, alright, that's not bad. But still, for 400 bucks you can use that cash and get a complete bike from Ebay. I'm looking into that myself.

I miss the old one when I get rid of it. I like the old bikes because they weren't so flashy, and you don't mind dinging em up a little. Get the work done. Just try to get a better deal or do the work yourself.

Seems like a lot of money for the work you've mentioned. Nothing on that list (and nothing likely to be wrong with a bike that hasn't been abused or crashed) is very difficult to do, and you'd save a lot by doing it yourself. The cost of bike-specific tools would add several dollars, but you don't need many and you're likely to buy them eventually anyway.
I haven't checked prices lately, but if you figure $60-$70 for tires (you can do it cheaper), $30-$50 for a cassette (that's mail-order price, not necessarily bike shop), probably just one chainring (I've never worn out the big ring), plus bearings, grease and odds and ends (new cables?), you'd be well under $200. An afternoon of work would probably do it.
Short answer: I'd resuscitate. I'm a decent mechanic now and could do the work myself, but when I started, I was COMPLETELY ignorant--I didn't know the difference between presta and schrader or that you could replace just the bearings in a hub or headset without buying a whole new assembly. It's not that hard to learn.

thanks for the replies!

got a call from the LBS saying that chain rings for the shimano 105 crank are not available (?), so if i want them to do it i'll have to go with a new crank for $150.

i'm going to pass on the option of having this shop do the work, ride the bike as-is, and regroup. might try the work myself but i don't understand the bit about the chain rings.