DEFINITELY attend your KCU interview.. you never know what school you will love until you visit!
MSU and KCU are both killer schools, and you can't go wrong with either of them, OP.
I received my MSU interview invite about a week after I was accepted to KCU. After researching the schools as best as I could for a few weeks, I decided to cancel my MSU interview. I had a bit of bias because one of my secondary goals when applying to medical schools was leaving MI.. but I made 100% sure it was the right choice before I cancelled MSU. I'll say this:
MSU will make research easier to acquire (affiliation with a large research institution) and will make IN STATE residencies easier to acquire (as will any school and their respective location...) If you are very interested in research, or you want to end up practicing in MI one day, MSU may be the school you want to go with (assuming you get acceptances from KCU and MSU.)
At KCU, you will have too work a little harder to get clinical research, but the opportunity is there for you. With regards to residency, there is obviously preference shown in KC to KCU students in the area (just like there is preference shown to MSU grads in MI.) One thing I loved about the KCU curriculum was that they place a strong emphasis on board-prep and this shows in their board scores (they kill it.) Obviously your performance on the boards will be determined by how much preparation you put into it, but there is something to be said for KCU's curriculum and reputation for crushing the boards (both COMLEX and USMLE.)
ALSO: (IMO) Kansas City >>> East Lansing. KC has much more to do than East Lansing. Don't get me wrong, EL is fun (I've spent quite a bit of time there in undergrad!), but KC is a big city with all sorts of diverse things to do that you won't be able to do in EL. So if you are looking for more of a city feel, maybe you'd like KCU? If you like the college town feel, EL is definitely for you though.
TL;DR: They are both killer schools... Attend the KCU interview (because, why not?) and if you're accepted to both, go where you think you will flourish most as a student (academically & otherwise), because that is what is most important!