open call: this falls MBP 15' graphic cards performance on openGL

this is another boring inquiry about hardware performance issues …

I’d love to have testimony about the differences in performance of the current graphic cards in the Macbooks Pro 15′, that is Radeon HD 6750M vs Radeon HD 6770M …

Is the difference worth the 400€ difference? thinking about mainly openGL things … that is not 3d but using those planes, slabs and shaders for quicktimes in PhotoJPEG_codec