I stayed there this weekend with the date and we had a really good time. I did the upgrade, and they gave us this great room with a spa tub, and everything about it was pretty clean (one of the chairs had a slightly noticeable stain on it, but that's all). The room was huge, probably larger than we should have stayed in, but it was fun.
I actually enjoyed coming here with her, especially since I'm kind of tired of coming to Vegas and got to see it with someone who isn't tired of it. Paris is about the right size for one of these theme casinos -- not too large, not too small -- so it's easy to walk around and conveniently located across the street from the Bellagio and their water show for the turistas.
Some of the restaurant choices are kind of weird (outside of the Eiffel Tower restaurant, which really isn't French, there isn't a French restaurant here), but for the most part it's a fun place.
The coolest part is some of the random music acts they have off the casino -- very classy and elegant for a place that doesn't always have a classy and elegant crowd.