I have also skied the prophet 90 and while they are wicked all mountain they are too narrow for deep pow and crud. I wouldn't say the motherships ski the same way. They are a lot more ski and like long radius turns. In theory, the subtle early rise should make them ski a little shorter than 195 but it's hard to tell. Not the best ski for making quick turns in trees but in the open they will plow through everything in any condition and go as fast as you are willing to go.
If you want a ski that handles the same as the 90 but fatter try the 100. It's a little bit softer than the 90 but other than that it is pretty close.