I also use a similar wireless MPG with similar performance - never had interference issues. I like the ability to use its magnets to put it where I like for one-handed operation, and I can use it while looking at the tool-workpiece distance, including moving between axis switch/step size switch/MPG knob. My concern with the three-knob device is how easy it would be to accidentally knock the wrong knob, especially as you will presumably still need a step size switch at least. My current machine came with some clever-looking pendant-like device that was almost usable when stuck to its Velcro pad on the control panel but was too light to put down and use one-handed. I quickly reconfigured to use my trusty wireless device. OK, familiarity counts for a lot but I would like to hear how people get on with this device. I can't twiddle two dials at once with any accuracy so would only do that for rough positioning anyway - and on my CNC machines I normally use the MDI input for that - so it's not immediately clear what the advantage is.

Have to confess that I'm also a bit influenced by a small whoopsy last night - knocked the MPG dial by accident and drove my touch probe into the workpiece. Have to remake the stylus probe - again... The idea of three knobs that might get knocked accidentally would worry me!