rapg,
Agree with Capt BK, I don't think you will be at any advantage or disadvantage whether you do the course on a Jet or a Turbo-prop Sim. I have also been told by a number of different sources that when being assessed on a sim check, they are looking for your basic handling skills, and your ability to improve throughout your flight details.
From my own personal experience, I chose to do my MCC on a full motion B757 sim. For me it was a nice way to finish after doing the IRT purely from the amount of fun I had, as well as learning an awful lot about CRM, and what it is actually like to fly a heavy medium sized jet.
Good luck with what you decide.