Ars Technica tests Aperture - and is less impressed by the program than by the size of Apple's manhood:
Jumping headfirst into the fully mature digital imaging market requires the shameless bravado of a one-legged man at a butt-kicking contest or any number of contestants on So You Think You Can Dance?
That's quite a vivid expression.
Based on the description, I'll stick with iView MediaPro - it runs well on old machines and does almost everything Aperture does. And where it doesn't, external programs do. And I still find Aperture's system requirements obscene.