The gear knob won't stay on those, I bought a car with one fitted so I know how annoying it is. The throw is also really short, even compared to the z3 lever.
I went for the z3 shifter and yes they have gone up a bit, but once in the bmw garage i was committed and glad i did in the end got the other little bits too like the white plastic bush thats worth getting too , i think mine came to £60 ish all in not bad considering its a proper quality product not some johnny snap off ,Chinese risk O shift
I just think it's a bit of a liberty the amount its gone up, BMW have clearly cottoned on to the fact people use them as an upgrade and upped the price accordingly.