Sort of. The 3x3x3 and 5x5x5 both have fixed, immovable centers. Red is always opposite orange, blue is always opposite green, and yellow is always opposite whi

Sort of. The 3x3x3 and 5x5x5 both have fixed, immovable centers. Red is always opposite orange, blue is always opposite green, and yellow is always opposite white. The 4x4x4 doesn't have fixed centers. When you build the central 2x2 squares on each side (the first step of the reduction method), you have to be careful to have the colors arranged in the correct locations relative to each other. In a certain sense, this is trivial, but it forces you to remember exactly where all colors are on a solved cube in order to solve a 4x4x4 (or other even sized cubes). Odd sized cubes don't have this problem. Another annoying thing about 4x4x4 compared to 5x5x5 is that you have two possible types of parity issues on the 4x4x4. On the 5x5x5, only one of these can occur. Nevertheless, if you know how to solve a 3x3x3 and no bigger cube, a 4x4x4 is certainly the easiest next step.