I stay out of contracts. Phones 2 months after release are cheap...and under warranty.
I tried the S4 when it was released, but signal and animation stutter (lag) was too big of an issue. ROMs can fix stutter, but not signal.
Also, really dislike PenTile.
Well there was lag but on mine the lag has dissapeared with the update luckily.
signal is shocking too but that is because who i'm with. vodafone are shocking but after getting the EE wifi portable connector battery life is alot better.