I just don't like the galaxy s3. I don't have a bias either way. I'll use whatever product feels right to me. Aside from the smaller screen, the 5 just seems 'right.' The construction seems far better and the interface far more polished.
The curved corners, the plastic, the large-ish, silly looking icons on the s3 just don't seem 'right.'
I just can't stand the idiotic fanboys on both sides who get butthurt if you don't choose 'their' phone.