I paid $700USD (500 quid?) for an Ecotric fat tire bike in 2019. I found it was very well made. Two years later, the battery is still good, the motor works, and nothing broke. It has all the same parts one sees on cheap bikes, 36V battery, Tektro Aries calipers, 3 level pedal assist, Shimano Tourney derailleur, cheap SIS shifter, steel wheels, but they're still good enough parts.

Now the concept of the bike is flawed. It's a heavy folding bike, but quite a lot of people my age like it, I'd never seen a fat tire bike with 20"x4" tires and thought it would be be smaller like my folding bikes with 20x2" tires. But it's a monster, OK sometimes.