Sorry it took me so long to reply back to this, for some reason I didn't get an email notification. I tried the Indivision but I just find it a bit of a pain to adjust. I have one in an A500.
I have a monitor that supports 15khz pretty well so I will just stick with that I guess. It tends to stretch things even if you set it to not use the native input size. It doesn't stretch the the 3k or a 4k that has an RTG in it, guess it just depends on the signal?
Mine does not have a slot so that's probably another reason just to leave things as they are.