Samsung s3 is a wonderful phone compare to Nexus 4.Even according to what you are saying,you agree with me that Samsung s3 has a lot to offer when it's comes to performance.
Though Sony Xperia Ion is nice phone but sony is not fast on update it's phone. Motorola Atrix HD will always get latest update because it is own by Google. Motorola Atrix HD is quit newer compare to Sony Xperia Ion. jroc21 go for the Motorola Atrix HD it's also a great phone.good luck.