Currently I have R500 (X1900) and R800 (HD5850) and as someone who already installed and readied 4 Intel systems (3 of which Sandy/Ivy), I would say radeon opensource driver is more than a match with Intel driver, except in 3D performance/watt.
Originally Posted by Ericg
The bare hardware performance is still sufficient to cover the gap of radeon driver inefficiency at 3D. So you can safely count radeon in, except when its laptop. But then - I have a R500-based laptop and its working pretty good, while some users reported Intel laptops to have power management problems...
AMD closed source driver was never something good, that's what AMD should nail at last in its own policy for good.