Charlie's apartment is in a prime location. It is within walking distance of Millennium Park and Solider Field. There are a ton of great bars and restaurants in the area. It is perfect for a place to crash while in downtown Chicago.
In addition, Charlie is the most responsive and helpful Aribnb host I've ever come in contact with. Over the course of the weekend, my boyfriend and I had multiple questions; Charlie answered each and every one within minutes. He is knowledgeable about the area and willing to offer recommendations.
My only criticism would be, and to be honest perhaps we should have checked first, is that the kitchen is not stocked with most essentials. The basics are there - a few cups, plates, and silverware; but, not much for extensive cooking.
As far as the train goes, it's really not that bad. It runs actively during the day, but slows down considerably after 10 p.m. I'm an incredibly light sleeper, so I was initially concerned. However, earplugs did the trick.