Oh and whats the difference between a calibrated open set and just open set ... theres like £70 difference
I assume you mean "calibrated open set" and "open-pole"...
"open" means that there's no cover - sorry for stating the obvious :? - and "calibrated set" means you have a set (that is, two pickups), and that they are made to work fine together, one in the bridge position and the other in the neck position. So you can either buy _one_ pup (covered or open), or a set - that is, _two_ pups - covered or open. And yes, indeed, buying two pups will cost a bit more than buying only one :lol: (but less than 2 times the price of one pup, and you'll be sure to have pup that match each other).
HTH