I've been doing standing barbell curls for a couple of months now but I find it increasingly tough on the wrists. I have flexibility issues due to a broken wrist years ago.

What should I replace them with?

I know barbells are superior to EZ bars because they allow for greater contraction, but how significant is that really?

I suppose I have a choice between EZ bar standing or preacher curls, or some kind of dumbbell exercise. Which will be best?