The mv6 is the sport model with a v engine. Sport model with a 2.2 engine is called, of all things, a 2.2 sport.
There was a facelift between the model years you mention so that will account for the vast majority of the differences.
But basically, a sport model in any guise will consist of minimal interior toys according to the fashion at the time of manufacture and firmer suspension to prevent role in the corners. Sadly the omega sport/mv6 did not get any engine tuning. No model did, including the plod cars according to legend here.
The items of value in an mv6, especially the facelift with lowered sports chassis, is the suspension, and possibly the leather sport seats. Hence the breakers don't see much value in them. But to drive, they are a world apart compared to the softest sprung omega in the range. The Elite.
If buying either an Elite or an Mv6 and your anything like me, you'll want the best of both worlds. So then base your purchase on your personal skills. If your good with electrics, by the mv6 and upgrade the toys.
If like me. Your crap with electrics and better with the spanners, by the elite and upgrade the suspension. Seems far easier to me.

Tbh, I would say, the mv6 is by far the best handling car in the omega range.