I have an international S3, and while it has a wolfson DAC I'm missing out on internet speeds. I have below 3G speeds..........it's horrible. After looking for another phone, and not wanting another S3 I decided to get a T-Mobile S2. I read a lot of reviews from people all around the forum about the horrible quality of the S2, it not having the wolfson DAC. The interesting thing is there are many variants of the phone, and T-Mobile appears to have the Wolfson http://mydragonboard.org/apq8060/. The good news is it is actually really easy to check. Can someone please open their terminal emulator, and type this command.
the result tells us the model of the audio codec. It worked on my S3 LTE, and I'm assuming it will work on the T-Mobile S2, if it does not I'll update once I get the phone.