STi has at least the following over a WRX...

Better brakes
Better diffs
Better gearbox
Better manifold
Better intercooler
Better hubs
Better driveshafts
Better seats
Better wheels

So it depends on what you are using the car for. Want a new car, get the WRX, want something that can take a beating, get the STi. (Check the motor very carefully on a 08 STi though!)

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[COLOR="Gray"]550Nm off a 2L... Just wish it was in the dak dak...[/COLOR]