I'm not sure how much help I can be as of yet, but I am a new M1 so fresh out of the app process - what questions do you have?
I will be attending the Wichita campus! Here's my understanding of the breakdown of your choices:
KC for 4 years is what you would consider the traditional experience from a large medical school. The largest portion of the class is here, there are multiple buildings, a dedicated teaching hospital,etc.
In Wichita, we have 1 main building (includes classrooms, support stuff, student spaces, a library, shared space with the pharmacy school, and a clinical skills lab etc) and will conduct some of our classes via IDL (basically webcasting connection from KC, although actually I see on our schedule some of the lecturers are noted at wichita or salina on various days). There are 28 of us who will do Wichita all 4 years. We rotate through 4 major hospitals - Via Christi St Francis and St Joe (Ascension Health now), Wesley, and the VA. We also have some community practice possibilities for rotation (like in clinics etc). Wichita campus slant is towards community practice based medicine, although that doesn't mean that your interests etc are restricted or anything.
In Salina, 8 students work primarily with Smoky Hill (the local hospital) and I believe the slant there is towards rural medicine?
44 students will also do KC years 1/2 and Wichita years 3/4, so they'll join us during the summer immediately before year 3. Rotations between all campuses are largely the same. Some electives are a bit different - I believe you can see our choices online if you look at the academic catalog for the school of medicine.
Most people want to go to KC. If you pick another option, conventional wisdom is that you will generally get that other option.