Trust me I will admit I am a Nvidia fan boy and I will never own a AMD card but that 5770 is a good bit better than the 260 and I'm not gonna lie to someone and say there's nothing better they can get for their money.
I only meant much better by thefact that it was only 5$ more
EDIT: really though DX11 useless? hahahaha I can't say I can see where you're coming from. Clearly you haven't owned a DX11 card.