Looking to purchase a powered lawn edger/trencher but cannot find much choice, there does seem alot more choice on USA sites.
The Mantis tiller has all manner of attachments available. I use the lawn edger and it works well for me. It saves a lot of time and gives a cleaner cut than using a half moon edging tool.
Lawn edgers dont seem to have the following they have in other countries, particularly the US.
@KT53's suggestion of a mantis is great. The Mantis is a brilliant, incredibly versatile little machine.
Similar results can be achieved with a half moon edger and for speed, maintained by verticle strimming (if you already have a strimmer... the lighter, the better), and isn't easy at first. But practice makes perfect!
I got the edger when we had the new lawn laid. I had over 200 feet of edging to do and clearly that was much quicker and easier with the powered tool.