@Jeff
The MorphOS website says that they recommend 128MB of video RAM as a minimum recommendation.
http://www.morphos.de/installation.htmlGiven that it from the devs directly it would seem odd for the 256MB 9200 or 9250 not to be the best, at least overall. (Since the 8500, 9000, and 9100 came only with up to 128MB according to Wikipedia).
http://tinyurl.com/5sk5kkPerhaps the GPU is not quite the same. But given that the devs are pressing the point of RAM and the 9200 and 9250 are the ones that beats that minimum best it would seem to be what they are instructing the user base to be the best bet.
