I've got the parkiside model that LIDL did on one of their specials, which sadly it means they don't sell them anymore, they do pop up second hand occasionally. It's almost certainly rebadged version of another existing cheap model, but it was £90. It works a treat.
FWIW, my dads a mechanical engineer and his take was that at the lower end, there's likely to be very little practical difference between any of the models around £100. I've seen near identical 24-50l clarke/draper etc. models pop up on gumtree/ebay for £40-80 in the past. Depends if you want to risk buying 2nd hand though, if -like me - you only use it for blowing up a few tyres, it's probably unlikely to go wrong any time soon.