I'm using Aperture but I don't feel that it deals with Noise very well at all. Does someone know of a good aperture Plug-In for NR? I Just don't like exporting a pict to another program for a fix and then back again. I did try LR 4 but while it dealt with noise very well, I found the rest of the interface Wonky.
I used Aperture but felt the same as you so I tried Nik Dfine and really like it. It works much better than Aperture noise reduction.
I would also say that the Nik sharpener pro is also much better than the Aperture sharpening tools. These two products have made my images better...no doubt about it.
Also, there is no importing or exporting with Nik...which I really like. When in Aperture on the adjustments tab, you simply hit the "edit with plug-in" button, and nik launches a new window in front of aperture. When you've finished, you just click the save button and the nik software quickly closes and the new and original image are now in the aperture...very simple and easy to use.