Yeah but if you have to go to the detail of making an offset map is it really worth debating that Card XXX has an image advantage over Card YYY? I mean, if you can't see any noticable artifacts when eyeballing screenshots I don't see how it's really a big issue.
You may be right in regards to image quality on that level but for me that wouldn't be a 'buy' or 'not buy' type decision. I'd make price, performance and support (drivers) my biggest issues.
I think if ATI can improve their drivers further (especially in the OpenGL realm) they will have a heads up on Nvidia but for me, now, ATI is behind Nvidia at this point.

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