[pugs]

The ball with lights systems do work (or pin or whatever style they have now), but they should be double checked for accuracy with an indicator every once in awhile. Read up on which ever one you think about buying as some use the part as the conductor to finish the circuit for the light going through the machine and back to the spindle. This means that they won't work to find edges on non magnetic part materials or possibly in machines with ceramic spindle bearings (probably not much of a problem on the manual stuff). I have seen a few of the lighted edge finders worked by detecting the ball or whatever moving off of a conductor in the body, these should work with plastic parts etc.

On my manual equipment I typically use a jump style edge finder. These can also be had in a jump and click style so that there is an audible clicking sound once the tip has jumped. I think there are also now some made that can "jump" farther than regular, so that it is easier to see as well.

The CNC equipment I have uses a renishaw probing system so I don't really get much use of the jump style. I don't own an electronic type edge finder, but did play with a couple in tech school and an old employer. The biggest problem I saw with the ball style electronic finder was you could get chips under the ball that would hold the ball off center a bit and then give you a bad reading. Easily overcome by making sure the area is clean of chips when used and keeping the edge finder nice and clean as well.

I have never used a wiggler, so not sure what is available for them.