I have been riding a Giant Iguana since June of 04, good bike, ok components. I have over 1700 trail miles on mine, replaced the front fork, (factory Manitou Six Sport, not the best), rear wheel, crankset, chain and freewheel.
The fork was not designed for my weight, (240lbs), so it cracked at the arch, and was contiually bottoming out. replaced at approx 400 miles.
In 05, I started breaking spokes on a bi-weekly basis, breaks caused by stress, no impact, so I replaced the factory wheel. Factory wheel held up for approx 800 miles.
I hit a rock and badly bent the big chain ring and slightly bent the middle ring. As they were braded in place instead of bolted, I replaced the crankset, chain and freewheel at approx 1200 miles. The chain and freewheel were worn and need replacement.
Given the price, and the fact that it was available in a 23in aluminum frame, I am please with the bike. The replacments that I have done are due mostly to normal wear and tear from a near 250lb mountain bike rider.