Most aftermarket wheel trims from Halfords, ASDA, etc. really do look awful and knock £s off your car. If the pictures are anything to go by these look more like OE trims (a couple of the styles anyway) and at £9.99 a set should be a cheap way to tidy up your car without breaking the bank if yours are tatty or missing. Also looks like they have proper secure 'spring wire' fixings like the OE ones (cheap ones often rely on the plastic itself). OE trims are usually £15 and upwards EACH!
I'll have a look when I go in to buy the screenwash!