I like the Z probe idea for bed-leveling delta printers. I have a Rostock MAX, and I got an Azteeg X5 just so I could see how good Smoothieware's autolevel is.
Unfortunately, there are no settings for me to tell Smoothieware the probe's offset, so it assumes the probe is at the extruder nozzle. In actuality it's about 50mm away, mounted on a far corner of the effector. Marlin and Repetier both have settings for this. When I run the bed leveling, it can get a calibration to within 30 microns, but since all the measurements are of points ~50mm from where they should be the result is terrible. It digs into the glass near X and lifts a good three layer heights near Y.
I looked through the source code but didn't see any provisions for a probe offset. (Basically, it would add the X/Y offsets and take the Z offset into account for bed height calculation… not terribly hard.) Is anyone working on this?