120Hz is a marketing ploy at best, imo. You really can't tell a huge difference in PQ, if at all... definitely not to justify the extra cost. If anything, I'd think the higher rating would just be easier on the eyes. I can't recommend the OP put that high on their list.
As for the previous samsung comment, to me it has its caveats. The upper end Samsungs do have deep black levels, but how accurate I couldn't say. They tend to have the higest contrast ratios and produce a very good picture, however it's been my experience that they tend to lack in SD reproduction, maybe it's that their de-interlacer isn't as good, I dunno, but the SD never seemed to look as good on them as it does on others that I've seen... then again, most only watch HD when they can help it, I'm the same way. SD is decent on my Sharp, about as good as I've seen on anything short of a Tube TV.