Hi Chris, I can't really speak to the semi/full apo catagory - although if I had outlaid a couple of thousand bucks for a full apo, I would be disappointed to see false color/fringing anywhere. I have put a video review up on youtube here:
https://youtu.be/TfZmL0XfTJk and at the end of that, there's a bit of video shot through the scope with and without the flattener. The end video of the tulips gives a pretty fair impression of what I see through the eyepiece. I also spend a little bit of time talking about the limited focus travel and how that may affect some diagonal configurations. Hope it helps!