I have recently returned to the PB trainer after one pair of extremes. Despite all assurances to the contrary I always felt that the extremes were a bit less close-fitting.
Don't talk to me about inov8's I tried on half a dozen pairs of them on Saturday before getting a pair that fitted.
I am certain they have changed the last for the 270, but that's off topic.
I quite like the PB Extreme, if only they had a bit more of a midsole for running on tracks, it hurts my feet.