They are both complex. I have to learn their routines section by section before I can do the workout as a whole. As much as I love Amy, I think Seasun's routines flow better once you get them down.
Amy sometimes confuses me as to which foot I should be starting with because she may throw in a transitional jack (whereas with Seasun, it is just automatic because of the previous move.) I hope this makes sense to you.
With this being said, I use Amy's workouts more. I have more fun with Amy. Her workouts are also intense without the dread factor.
Good Luck. It takes awhile to wrap one's head around complex choreography, but once you learn that first step routine, it does become easier.
Lisa