I carry both as well.. I use the One X as my business phone and the S3 as my personal device. The screen on the GS3 is great, as long as it's not side by side with the One X. The color temp is much colder on the GS3 and the reds look way too saturated to me. They both really are awesome, but at the end of the day I'll be using the GS3 as my personal device. Also, the GS3 in person looks a lot better than in pictures. For my liking, if the One X was a little less buggy and had no lags I would stick with it. As I mentioned before, however, Samsung has this Android thing on lock right now. They have the formula for the best Android device on the market once again.
Shoaling,
-Showking
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