However, I also believe it's not always possible to judge the quality of something purely on its price. Hopefully these are "stuff sold at a loss, clearing out someone's stores" rather than "engineered down to allow a healthy profit even when sold at £4" !
It's a few simple pieces of stamped steel, I'd think it possible to make it cheaply.
There was also a "known to me" brand "Maypole" branded tow hitch available for about twice what I paid:
(One listed at £7.50, but seems sold, here's another at £11.99 Inc postage:
https://www.ebay.co.uk/itm/176701653188 ... media=COPY
And same brand is available from EuroCarParts for £16.99
https://www.eurocarparts.com/p/maypole- ... -551774050
I'll report back on what I think of it when it arrives (including if I think I've been a fool and wasted my money!