Have owned two of them. One with electronic viewer, one without.
The NEX-7 with viewer- did not like the view. Found it to be low res and kind of jerky and not what the scene really looked like.
NEX-3 - no viewer. Hard to see the image in bright light which is where I usually shoot. Has a Mickey Mouse screw on flash.
Both take excellent photos, both have a pan feature which I like. I also
Like the live light spectrum read out. Allows you to crank the f stop to get the exposure you want.
Traded off the NEX-7 for a Holy Smith. My only Holy gun!
I still like to look through the hole and view the scene through the lens.
Presently shooting a Nikon D-5100, in the market for a D-7100.