I agree with Raiyn. The bike is old enough it's worth switching to a new frame so there's no need to worry about fatigue. The Jett is relatively short travel (63 mm?), whereas the standard XC lenght now is 80 mm. It's not a huge difference, but it will affect the handling a little bit.
For the price range, I'm inclined to say go for the 6500 or an equivalent hardtail, unless you think you'd benefit pretty significantly from a full suspension.
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