For £50 the cards are "greatest" at a particular thing. One may be better at driving multiple displays, one may have passive cooling and be best for a quiet home theatre system and one may be clocked higher and better for gaming and be fan cooled.
It strongly depends what you want the card to do in this price range.
i got a gtx 1080 in a custom built pc last. used it on gtav,witcher 3 diablo 3. a simple looking game that demands a lot is witness. using a few monitoring programs i have never seen the card work more than a third of its power. to put it simpler ,,,, there is nothing out there yet to put it through its paces ,, unless of course somebody knows different.