hi, i don't really know much about bikes but i'm really interested in starting. My price range is generally around $400-$500 to get an entry level bike, and after going from one bike shop to another these are the bikes which my local bike stores have :

GT Avalanche 3.0 2005 ->http://www.gtbicycles.com/mountain/c...usa&brand=moun
Giant Yukon 2005 -> http://www.giant-bicycles.com/us/030...sp?model=11039
and the Scott USA Montana -> http://www.scottusa.com/product.php?UID=6101

As far as the feel of the bike goes, I can't really differentiate one from the other, however it seems to me that the scott montana is the lightest among them. But after going through the whole thread I've only seen it mentioned once and nobody seemed to ellaborate on it. Is it any good? Which of the 3 would you guys recommend

EDIT : oh and also, I was thinking of maybe upgrading the bike as time passes by changing the parts on it. Would doing something like that be worth it? And if so, which bike would you recommend?

Thanks in advance