It´s absolutely the Jp who´s the winner in my oppinion. First of all. I have own both those machines. And I think An 1 x is just a plastic toy with the worse digital sound ivé ever heard. The Jp sounds quite digital too but this machine has got a pretty warm sound.Nice Pads and good bass sound.
I say if youre looking for a An 1 x guys why don´t you take a look at the Cs 2 x which got it all the way. A lot of samples lovely pads and strings and some amazing basses and its absolutely a great Dance/Trance/Club synth.
If you like to you can hear how the Cs 2 x sounds like.