I just purchased my tractor (see signature line below) with the BH75 backhoe and this nifty Wallenstein Thumb (it fits this hoe very nicely). My main concern is that, though it appears to be fairly beefy, it might bend a bit with use. If it does, then the holes it uses to fix the thumb at various angles (including the ones used to tuck it up tightly against the dipperstick) may not line up well enough to get the pin inserted (time will tell). I suppose a good file will help to alleviate this if it becomes a problem.
I'm considering the possibility of adding a strengthening rib to it provided I can figure out how to do it without impacting its functionality. I can say this though - it really is a nice looking unit (which is why I bought it).
I'll post pics when I get the chance (lots of fallen trees to pick up and move around as a result of this noreaster (the heavy snow took out several of my hemlock trees).