I've had a DVDO Edge and now a Lumagen Mini3D. I have to say that IMHO the upscaling is better with the M3D than my Edge, which IIRC is the same upscaling as the Duo. There was some ringing on SD stuff with the Edge, but the trouble is that you're never really sure if it's EE in the source I suppose, so you need to take that into account. The other thing is screen size/viewing distance as I'm 112" wide (2.35:1) at 11-12' viewing distance. When viewing content on my TV from the same distance, it really didn't matter as 40" from 11-12' make it hard to really tell.
The other issue is that with the Edge it would be complicated to get say a 480p output for SD sources and a 1080p for HD ones, without going into the menus and changing it each time so that your display can upscae or not accordingly. With the Lumagen, you have so many memories available (and input resolution dependant memories too) that it's so easy to set up exactly where the upscaling and deinterlacing occurs. Ironically, this flexibility is moot as I've found it best to feed the M3D with 'source direct' and let the M3D do the deinterlacing and upscaling as required.
"Don't believe everything you read on the internet". William Shakespeare 1615