I bought my Aveo for $2500. It had a freshly rebuilt head and new timing belt. I put about $1000 into over the course of the next year (brakes, battery, tune up, new suspension, tints, etc). I put about 10k miles on it per year, so it would take me another 5 years and 50k miles until I even THINK of having to replace the timing belt again. And at that point, I'll probably just drive it until either the timing belt snaps and sell it for scrap or until the clutch gets worn out, which I don't see in the near future anyway.
I love the car, but I'm not obsessed with it. Its great at what it does; being a cheap, reliable car that gets me from A to B, that saves me from putting miles on my gas-guzzling, high cost maintenance Jeep. So my vote is to drive my Aveo until it breaks and is not price sensible to fix.