Just wondering what people's views are on these cheap (£500/£600) 3pt linkage hole borers. I'm sure they're brilliant in light sandy soils but how well do they work when the going gets tough (stones/roots etc)? And also how durable are they in these conditions? I know there's not a lot to them but at £500, I'm suspicious about the gearbox! Also, how long do the augers last before they wear? Any comments from anyone who's bought one would be much appreciated!