Buying a EVO... NEED ADVICE

Well, I've been researching my options on buying an EVO.. Orginally I was going to stick with a 2003 EVO 8, being they are the cheapest option: But then after a month of 2 of thinking...I think I will rather invest in a MR. Now occording to my research, the MR is only available begging in the 2005 Evo 9 models and are rather expensive... so, are the MR's really worth the price??.. or should I stick with the other Evo models that are available.. I only know of the RS and the GSR.. thanks in advance.

I am no Specialist when it comes to the differences between the Evo VIII and the VIIII/MR. From what I understood, the only difference is the Center Diff 3way switch, the 6 speed tranny, and the rear difuser over the glass. All of those are only available on the VIIII from the factory.

I just purchased an 04 with 50K miles on it. I looked to at the MR/VIIII as well, and just couldn't see the added cash for the differences at the moment.
Besides, I am sure the 6speed tranny could mate to our motor, and drivetrain. Not sure about the center diff conversion..?