I am fortunate enough that the Cereal Killer Grain Mill is provided by my LHBS Adventures in Homebrewing. I can say they are a top notch business. As a matter of fact they just opened up a second location in Ann Arbor, MI. I inquired about this Cereal Killer and it was explained to me that a big reason for this new mill was because they could not procure the Barley Crusher in a consistent enough manner to keep up with the order demand coming through the store.
On Friday Oct. 28 I visited the store and was able to compare the Cereal Killer and the Barley Crusher side by side. Both mills come with a crank handle, metal hopper and a base to sit on a bucket. When it comes to the actual roller mechanism a person would be hard pressed to see a real difference between the two. They both have a thick aluminum base and adjustable knurled rollers (only passive roller is adjustable). The Cereal killer uses two thumbs screws as set screws. I liked this feature because it is nice making adjustments without using tools. There is a difference in the length of the crank handle. The Barley Crusher handle is a couple of inches longer than the Cereal Killer's handle. At first I thought the shorter handle was a negative because it was obvious there would be less torque. However, it also occurred to me that a shorter handle on the Cereal Killer would actually increase the RPM'S making it produce crushed grain faster. The shorter handle might be a perfect balance between torque and speed but having never used either the verdict is still out. However, using a drill on either of these would of course negate any differences in the handle lengths.
The Cereal Killer really shinned through with the superior workmanship on the metal hopper and base. My personal opinion is all of the metal work and base of the Cereal Killer appeared to be very uniform and built with a much greater tolerance than the Barley Crusher. Some of the fitment points, rivets on the Barley Crusher seemed sharp/uneven or to put it plainly it gave the impression of a rush job. I can't say that the "look" would make the Barley Crusher any more/less effective but if you were to pick one out for the showroom you would definitely pick the Cereal Killer.
One last note. The Cereal Killer is not a Chinese made knockoff. It is manufactured right here in Michigan. If anything I would consider the Cereal Killer to be an improved version of the Barley Crusher idea.
Will head out during lunch tomorrow to pick up the Cereal Killer Grain Mill. I can give you further feedback, after using it, if anyone wants to hear about it.