Re: Benefit Cheats..
I think that I would stop short at reporting someone.
That's because I don't think it's possible to know all of the facts.
On the other hand, I might well write a letter to someone in power (MP, Council, etc) to enquire how I might apply for the same benefits as Joe Bloggs, across the road, as he seems to have a more beneficial scheme than what I have.
Or, maybe, I'd check in with the local CAB.
One thing that always "amuses" me is how expert, some people are, at understanding every twist & turn of the benefit terms & conditions!
There ought to be a college degree in benefit techniquews.