Are you talking about performance set ups Diki? The ES does what the MM cannot do and that's create a 16 part performance (that you can name) and customize the crap out of. Performances on the ES can include preset patterns, arp settings, effects settings, mixer settings.., the list goes on. This is a very common mode used by players who perform in a worship group and use a workstation.., or even a performance synth. It puts 16 patches (presets or your own) along with many other edited parameters in one performance. You can use the track/part buttons to have all 16 patches at your fingertips.

if you can trade in the ES and then spend only a few hundred dollars for the MM8 and you get the piano weighted keys which is what you prefer then its less of a difficult decision.