Anyone one using an ebay: "Electric Edge Finder"

I was thinking about buying one and trying it out, anyone have a experience with using one of these?

I have one and they do work but haven't used it for ages.
The issue is they stick out of the spindle very far.
Unless your x,y table, column and spindle are dead straight to each other it isn't great.

These days I do it the slow way.
Use a short peice of 6mm (broke end mill shank) in the collet and a 0.02mm feeler blade on the part for both x,y, axis
Jog 0.01mm a time up to the blade with spindle running until I feel it drag. Remove blade and come in another 0.02mm.
Set 0.0 there then add or subtract the shank radius (3mm) into mach 3 dro.
Now the spindle center is +0.02mm from the corner at worst.

My column had to be tilted on my new machine to square up my Y axis.
The distance on my Y axis from corner of stock edge would be too far off because of the length of this tool..

I have one fixed to a TTS holder but have never used it. I use a Wildhorse Econo-probe 99% of the time. Also have an SDA center/edge laser finder with concentric circles and a small center point. The electronic touch-off one I use most is a Borite with a 3/8" shank and a 0.200" probe end.

As mentioned above, those 18 mm shank imports are pretty long. I use one on my Bridgeport.

Bruce

I've got the tormach one if you need one. Don't have my machine, but still various tooling