Are you getting the plenum mixed up with the lower collector? The plenum chambers are virtually identical between the 2 models, apart from a few bolt holes.
The difference is in the lower collector. The up-rev collector has shorter inlets, which would give you slightly less torque. You'll have absolutely no benefit fitting an up-rev lower collector whatsoever.
If you had an up-rev engine then a good mod is to fit a MREV2 from a MY03, which has had the front 2 inlets machined down, and a spacer