All,
I just got my scanning probe and found that it would scratch the paint off surfaces and many others were having this issue as well.
I found that if I put a model glue applicator tip (the ones you use to apply plastic model cement) it won't scratch your surface or leave any marks.
It fits nicely on the metal tip, blunts it, but doesn't add that much area to cause much concern in loss of detail. I've used it for only about 2 hours now, but I haven't seen much loss of plastic on the tip so I think it will hold up well.
I'm running an 8 hour scan tonight and I'll update it with my results. These tips are only about $2.00/5 so they're pretty cheap to replace as well.
The results have been as accurate as I need them to be, considering that you can only carve to a 1/16th in. with the ball tip carving head anyway.
Let me know if anyone else has a better idea.
Thanks!