DxO is kind of a one-trick pony: a slow, clunky post-processing app that’s only really good at doing one thing–processing RAW files. But it’s a REALLY great trick! I certainly wouldn’t choose DxO for anything other than RAW development and lens-correction. But, I’ve wrung more “quality” out of my Nikon 12MP D3s files and older Nikkor glass using DxO than I had ever imagined possible–the difference obtained using a DxO-profiled lens vs. a non-profiled lens is dramatic.
I use Aperture for 99% of my stuff out of sheer convenience, but for special images, I’ll turn to DxO. My poor, neglected AF Nikkor 14mm f/2.8D ultra-wide prime finally received its own DxO profile just a few months ago (DxO only had a profile for the 14-24mm previously), and my old D3s-shot, 14mm f/2.8D files improved significantly when using the new correction profile: