We purchased this bike (with front suspension) for our 8 years old son. It is slightly bigger for him, which we knew. He can grow with the bike for many years to come.
Only complaint we have about the bike is that the gear shifter is very stiff and hard for him to adjust while riding.
This bike is AWESOME!
We bought this for our 7 year old for Christmas. He's 49" tall with relatively long legs, and it (barely) fits him. He should be able to ride this for years to come. The components are fantastic on this, it looks great (though we would have preferred a lighter color), it's very adjustable, and the price is far better than any other bike of this (or poorer) quality. My wife & I bike every day, and we're a little jealous because our son now has - without a doubt - the nicest bike in the family!