The Petzl Luna is one of the heaviest harnesses that we tested (15 ounces), but it doesn't seem to have more padding than other harnesses in our lineup, nor was it more comfortable to hang in. Petzl recommends this harness for mountaineering and ice climbing, but we preferred the Arc'teryx AR-385a for those applications. The Luna isn't well suited for trad climbing either, as the rear gear loops are small and out of reach, and the leg loop buckle is painful to chimney on. Really, the Luna is just an adjustable leg loop version of the Petzl Selena and is more suited to sport climbing.
Petzl updated the Luna this year. See the latest version in the photo above and scroll down for the details!
There doesn't seem to be much different in the design of this harness and the men's version (Petzl Adjama), except perhaps a slightly longer rise (the distance between the leg loops and waistbelt) and of course a "girly" color (not that there's anything wrong with that). Ultimately, this harness comes down to a matter of fit. The women that tested this harness that had a short rise and more straight-cut anatomy liked the fit. Those of us with hips and/or who like to wear their harness on their waist did not. If you are looking for an all-around harness with adjustable legs, we'd recommend our Editors' Choice winner, the Camp Supernova.