AFA strickly drum/sampling/sequencing, i feel the 2K/XL more like the classic 60/3K with more features, those models were made as
"sampling drum machines" very similar IMO...
4000 is an other story, Akai finally produced a synth/workstation in a MPC box!
I've tried the 1000 @ my man crib, just to compare how the workflow's...
No offence deh, but @ first it was a lil' weird... but NO>>> MPC1000 is for the purpose of
"Laptoper's" 
, so you might have a wave editor on your laptop, cuz you might be a laptoper (sounds commercial no?)!!
IMO the mpc1000 is like half way between the XL and the 4000, but it wouldn't do it for me at all, i can flip from XL to 4K daily, but I just don't feel the 1000.