D700 portrait photogs...what PP software???

I have done a few portrait sessions recently, and am getting good (not great) results from Lightroom 3 from my D700 RAW files. I see posted on other photographer's websites and blogs portraits that have a certain look that I have a tough time pullling off in Lightroom. I suspect that many are using other software to get these results. Portrait Professional comes to mind as one that could be used by some. I have considered purchasing it, but am not real sure.

The best way to describe what I am after is this: deep yet subdued color, looks underexposed a bit, but it really isn't (faces are bright and clear), maybe a bit of grain or fine "streaking" to the entire image on some shots. It's tough to explain, but I can only get close, I can't seem to nail it. I use shadow clipping to deepen the look and try to control saturation and WB to get the color right, but my colors just seem too bright or excessively colorful or something, not subdued yet rich like I want.

What is the secret to getting that "look"? What am I missing? People like my shots, but I am not satisfied that they look as good as they could. Please advise...

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K.B.