I'm not sure if you're taking the morning run or the afternoon run; I only have experience on the morning run, and I actually board in Kirkwood. I take this train 3-4 times a year. It is a fairly smooth ride the entire way, and the on time performance is very good; in fact, the last several times we have arrived into Kansas City early! In fact, the only time we had to wait for another train was when we met the eastbound headed back to St Louis. You will be going through several small towns and rural areas, but being a farm kid from Iowa, I think that is pretty nice scenery. It doesn't appeal to everybody though! You will follow the Missouri River, and it will be dirctly on the right hand side of the train as you are heading west, until you hit Jefferson City, where the river and the train separate by a few miles. They have a somewhat limited selection in the cafe car, but I've always found something to eat. A few breakfast choices, a few lunch choices, coffee, soda, water, beer, etc. I believe that there is a menu posted on the Amtrak site for the route, but I haven't looked lately. I usually grab breakfast at a local restaurant in Kirkwood, MO before boarding, and then have a light lunch about halfway to Kansas City.
I almost always opt for business class, as I'm trying to do a little work on the way. There is 2-1 seating in the other half of the cafe car, it is a bit quieter, plug ins at every seat, a free newspaper, and (usually) a free non-alcoholic beverage (I say usually because they sometimes forget to mention it to the passengers). I have done it in coach too, with no issues.
If you have any other questions, feel free to ask! I'm not expert, but I'm pretty familiar with this route.
