They're all locked to 30fps so both of the mid gen refreshes should have no problem hitting 4K and many PC GPUs probably can too. Go with the one you like the control input for the most.
There's conflicting reports, even from official sources. It was at least 1080p with a ton of MSAA which is still pretty awesome for the PS3 hardware.Wasn't it 4K on the PS3 downsampled? Or higher than 1080p downsampled?