I have a blue Mountainsmith Ghost pack. This one came out before the green model and is slightly larger, has more durable fabric, and has a much wider, more comfortable hip belt. The pack weighs 2lbs 9oz on my postal scale. I believe its a size large. I'm 5'9 34 inch waist and it fits.
I've actually only used the pack on a few trips (usually pack too much), which tells me that it may be time to let it go to someone who will get better use out of it. A small amount of the fabric is slightly worn on bottom of the pack where the bottoms of the support arch rest on the ground when the pack is set down. I also see two very small (smaller than an eraser) worn areas on pack bag. There are no holes anywhere.
I would be willing to sell for $80 + actual shipping cost to you. Let me know if you are interested. Email me brycenerland at hotmail dot com.