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Both screens are high quality and I think that it's still true that there is yet to be the perfect display technology despite what the blogosphere says.
That leaves size and I agree it matters when using your phone as a PDA.
I remember when we all got our 4.3" Evos on Sprint and others got the 4.3" DX on Verizon back in 2010 and people were calling us crazy for having such behemoths.
I've been very highly satisfied with my 720p 4.7" screen since I got it (and got rid of the nav bar lol), so regardless of whether one screen is better than the other, if both/either match/surpass what I have now, that's fair enough for me.
I fully expect to get flamed for this - but - the draw for me on the SGS4 screen is that it's 1080p. The 720p/Pentile screens are noticeable and somewhat unpleasant for me. I don't have magic eyes that can see dots - I do read a lot of eBooks, I've tried it on the SGS3, and the text is simply not as crisp as on my 720p LCD.
I expect no difference going from what I have (LTEvo/One X) to the One screen-wise. The resolution/clarity on mine is already at the limit of my visual acuity. It isn't on the SGS3. I expect that will be on the SGS4.
I prefer more neutral/natural colors rather than vivid. That's a preference, but it's what I already have.
And the SGS4 allows for color adjustments now, so I won't be stuck with just vivid.
Put those two screen factors together, and all else being equal, the upgrade for me screen-wise is really size only. And being happy with what I have now, the screen is just a don't care for me all around.
IOW, going from 4.7" satisfied -> 5" satisfied just isn't a driver for me.
So, I'm actually comparing the sound feature and the esoterica as well as the other standard features.