Section 421 was awesome; it came highly recommended from a friend of mine who went with me. He usually buys the cheap tickets and sits behind home plate in the Hy-Vee seats as they're called at Kauffman. We obviously weren't close enough to be able to call balls and strikes but with every ball that was hit, we could see it travel really well. Very easy to follow the game from these seats but just beware that there will be a lot of steps to climb no matter where you sit.
Via the escalator is the easiest way to reach the Hy-Vee level. If you enter thru Gate C behind home plate, there will be an escalator that will take you right to your seats in 421. An usher will usually greet you and ask if you need any help finding your seats. This is one of the more desirable places to sit on the top so expect a big crowd here for almost every game. Most fans will be focused behind home plate.

"The K" is a very underrated ballpark, especially for a place as old as this one is. I think because the Royals never get any prime time games, they don't get a lot of love and not many fans know about this stadium. Hell of a place to visit, though.