I've used Pixelator on my current project Coma State Eden, only in a few places so far. It's a well made tool that gives good flexibility and options for how you want to adjust the source image when translated.
My game isn't being sold yet (it's a little over halfway done) but will be commercial when finished. Since I know I liked Pixelator I figured it was time I bought the license before it was commercial.
I would absolutely recommend Pixelator. It's handy for serious projects and is also fun to just mess around with for personal stuff.
Tip for those who want to preview pixelator:
If you feel the results of pixelator don't visually match the aesthetic of your project enough, you can always take the translated image and then do touchups yourself. Most of the leg work is done at that point.