In reply to CantClimbTom:
> Heavy duty carrier bag or rubble sack plastic - is your friend.
In what way? I've made a number of home made anti-balling plates over the years, but finding a way to keep them attached to your crampons is surprisingly tricky. I don't see how bits of a rubble sack would stay attached for a day of crampon use, let alone longer term.
OP - I've yet to find a problem with more modern purpose made anti-bots. I've had these CT crampons for well over a decade. https://www.ukclimbing.com/gear/snow+ice/ice_axes/climbing_technology_nupts... They get some use each winter and, for various reasons, I'll often use them if I know I'm going to be walking over rocks a lot (lower snow conditions typical in the Lakes and Wales, as opposed to Scotland). The anti-bots are scuffed and worn but still work perfectly well and show no signs of breaking. But then again, my main technical crampons for climbs are BD Snaggletooth, and I've had no problems with the anti-bots they have on, and I've had them for something like 7 or 8 winters now. The early 00s ones that were more rubbery would perish and break (seen it with those on my Grivel G12s and DMM Terminators) but now most manufacturers seem to use a harder plastic this doesn't seem to be an issue.