Sadly I had to notice, that Aperture (3.4.3) takes about 5s to show D600 raw images (24MP) vs. about 0.5s to show D300 raw images (12MP).
The timings are for selecting an image => “loading …” appears & all procs are at 100% => “loading …” disappears & the image control sliders begin working.

I really didn't expect the difference to be this huge :(

Does anyone know of some helping tweaks I might have missed?
Any suggestions are welcome …

I'm working with Aperture for six years now and I really don't want to switch to something else, but the lack of responsiveness after image selection is *very* annoying :(