I've often wondered two things:
1) Should the Phillips CDI be included in a Nintendo collection?
2) Should the Neo Geo Pocket Color be included in a Sega collection?
Also, are there any other systems that are strongly associated with another company?
I wonder this because I always considered the NGPC the successor to the Game Gear. It was to the Dreamcast what the Game Gear was to the Genesis. You could connect your NGPC to your Dreamcast. It shared games. It was heavily featured in the Official Dreamcast Magazine.
Also, when I collected Nintendo, I was always curious about the CDi games. I knew they were bad. But a Zelda collection never seemed truly complete without the CDi Zelda games. This leads me to wonder if the CDi should be part of a proper complete Nintendo console collection due to the history.
Of course, each collector has their own definition. Just like every full set collector has a different definition of a "full set". Just curious what others thought of these examples.