I would go with the Sony Ericsson.
1. you don't need 3G unless your going to pay for a data plan.
2. the sony has a 2.0 Megapixel camera to the samsungs 1.3. I know you'll enjoy that moe.
3. Sony Ericssons have a good reputation for reliability
4. SE makes a better MP3 player software than samsung
5. The SE looks better
