I love Aperture.
I'm loaded up with CS6, LR4, and Aperture 3.
I suppose I should, but I've yet to devote much attention to LR4.
I use DxO Optics Pro as a RAW converter. I make most adjustments when needed in CS6. I make some minor adjustments when needed in Aperture 3, which I think has come a long way since the first version. The most recent release I think is quite good. Plug-ins I use most often are Nik Complete Collection and onOne Perfect Photo Suite 6. I love Nik's products. Silver Efex Pro 2 is just outstanding for black and white conversion. I don't often shoot HDR but when I do I use Photomatix Pro, although I'm about to start playing around with Nik's new HDR release.
A great resource for Aperture information is www.apertureexpert.com