No they are not the same machine, two totally different companies.
Are they any good? It depends what you want the machine to do, I am guessing you want to cut long grass. The Allen scythe was primarily a grass cutting machine, although other attachments were available. The Barford Atom was a multi purpose machine with cultivating implements and a cutter bar amongst the range of attachments. Barford also made the Councillor Power Scythe, which was very much like the Allen Scythe.
I have no experience of using either for cutting long grass so cannot comment on their performance.
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