Cheers, will have a look, is there really that much of a difference?
I'm guessing that they last longer.
It's partly that branded stuff will last longer, and partly that they will also do spares for a minimum of like 10 years after you buy them. It may sound silly, but if in 5 years time one of the cartridges goes in one of the bath taps you bought from x shop goes and you can't get a spare then you need to buy whole new taps and fit them. Which is usually a pain with the bath in situ.
As Gilly said, you can get Bristan and other makes in the B&Qs etc, but just hunt around for a decent price.
Well just found out from my mum (yes I'm helping them to buy taps )
that the shower mixer tap we bought from wickes was £100 and the pull up knob thingy that switches between tap and shower has broken, we've had it for 5 years, so not that long.