The Akai is the easiest to learn. Go to a store that has them all and they will probably tell you the same thing. The Yamaha and Roland have other things going for them, like better effects or more substantial mixers than the Akai, but the user interface on the Akai is laid out in such a more logical way. I hardly even had to open the manual before I had finished my first project on the DPS16. The Yamaha interface might be good after you have learned it but it is really deep. I found the mixer confusing but that might be because I've never owned a digital mixer. I was never going to buy the Yamaha because the price was too high for me. If I was going to spend that kind of money I might buy a computer-based system instead.
