RE: DX10T
Yes.
Use one mix for each control surface. Use a 3-position switch and you can make it snap left, normal flight, or snap right. You'll need to adjust the amount of travel you want for the snap.
The momentary switches on the DX18 are only on the sticks, so it's hard to push them while controlling the sticks (for me, anyway). That's what makes the 3-pos neat because you can make it go either way.
NOTE: On these radios you can mix a switch directly to a channel, you don't need to assign it to a channel first.
Andy