[doughboy]

it does seem that from 04/10 on the ARB comes with bushes. But they can't be 'glued' on as, they have to rotate around the bar?

The newer models still have a 26.5mm bar, so you should just be able to buy a pair of bushings from an earlier model and use them.

Mines a 2009 LCI and birds bmw used the standard bushings and put them on my hartge front ARB, which is 28mm.

Yes a bar can be stiffer even thought its is the same size, it would depend on the grade of steel used, but i can' see why bmw would do that.