I made the move from A-Frames to Crowbars this past spring. Found the crowbars to put more pressure on my nose, however that did fade away after a bit of usage as the foam got adjusted and broken into my face.
Otherwise, I did not find much of a difference in the fit. They definitely work better with helmets than my A-Frames, so I will give credit there.
If helmet fitment is important, go with the Crowbars, but if you don't care as much about that, just stick with A-Frames because performance-wise, I noticed no change from the A-Frame to the Crowbar.