My vote goes to the i3 4150.
1. Lower TDP.
2. More energy efficient.
3. Much stronger single-core performance.
4. Better upgrade path.
That said, I'd recommend you save your money and go for an i5 instead. More and more games are utilising (and requiring) quad-core processors, and whilst the i3 is hyper-threaded, it doesn't perform at the same level as an i5. Remember, a core and a thread are not the same, and software will treat them differently.