I have this set. It may not be 100% accurate but it is a great looking set. The sounds are awesome. I grew up with the KCS and I think the sounds are exactly what I remember the locomotive sounding like. The paint scheme is darn close. I am very pleased with my units.
I changed my mind on these. I saw a set in person in a setting with better light, and the colors are pretty close, much better than the recent Lionel E9 set (that includes 2 A units when KCS only had 1 E9!). Since the price was really fair (cheap!), I bought the MTH E6 ABA set. Further research indicates that this was the scheme used from 1952+. I really like the radio antennas on the A units, a nice road specific detail. Not sure why MTH forces us to buy the B unit, though, since it is not at all prototypical (KCS never had any E6, or even E3, E7, or E8 B units), so my B unit stays in the box.
This is a much better effort by MTH than the Florida East Coast E6 set that I also saw for sale. With that paint scheme, the FEC set is supposed to be an E3, but does not have the correct paint details (black pinstriping, etc.) that Lionel included on their E3 set (from the Champion set) several years back.