I've done role-playing exercises as a rep and as a sales leader with my team. It seems to work well but the sales reps don't like it because its stressful. If this makes it more stressful, my team won't use it.
Because the sales reps are able to practice their selling stories or talk tracks in their home office / conference room / desks with SharperAx, it lets them focus on learning vs. performing. Only when they get a version they think is good do they share it for coaching. This takes most of the stress out of role-playing and it still gets the reps confident and credible.