Radeon 5850 vs GeForce 470?

Hi guys,

Going to upgrade my graphics card.

The 470 is ~$100 more than the 5850 here in New Zealand. Not sure if it's worth it or not, could anyone help me out?

I'm upgrading in advance until next year where I can upgrade my motherboard, CPU, RAM etc.

Feel free to make some suggestions if you have any :)

Update: Now it's Radeon 5850 vs Radeon 6870, leaning towards 6870. What do you guys think?