You have 13 notes per preset on the 12step. To switch presets you need to press and hold SELECT, release it then press ENTER, and navigate up and down with d# and f# to select the preset decade (the x part of xxy). You complete the preset number pressing of the numbered pads (0-9).
from the manual:
For Example: To move to preset 26. Press the Enter Key while in select mode and use
the -10 or the +10 key pads to increment or decrement through preset decades until you
see “02_” on the display. Then hit key 6 and you’ll be taken out of select mode and into
preset 26. The next time you go to change a preset you’ll already be in the 20s decade so
if you’re going to another preset in the 20s you can just step on the numbered key for the
last digit.
I don't personally use presets, but this sounds like It could take some getting used to, unless you stick to a single decade (10 presets). If you do, you can skip the ENTER key and the decade navigation and simply hit the pad corresponding to the preset you want, once you're in select mode.
Latency is not an issue with the 12step, however, you should really try the pads before you buy. It feels very different from the hard clicking switches you are used to and may prove too difficult of a transition. I can't play it with shoes, I never know whether or not I'm hitting the pads.