Posted: 21/08/2015 at 08:47
I've got one and it's the best investment I've made in years. It is a modern 4 stroke model (I understand some of the older one's are 2 stroke and can be problematic), very easy to start, extremely quiet (my neighbour didn't realise it was running whilst I was chatting to him) and light to carry around.
Stones haven't caused any damage, it either bounces off them or the catch between the tines - a quick whack with a hammer gets them back out easily enough.
Our ground is quite light, I don't know if it would manage clay soil. I've used it both for preparing the soil by deep digging and for loosening weeds. The depth it digs to is different depending on which way round you fit the 'cutters'.
I also purchased an attachment for edging the lawn. A new lawn had been laid quite recently and the idea of edging well over 200 feet of border by hand held no great appeal. With the edger I had the lot done in about 10 minutes.
I also use it now to dig over my neighbours veggie plot. He finds digging it over hard work now at 77. My neighbour on the other side has used a Mantis for years and it's still going strong.