After accidentally leaving my Holland rear bag sitting on the edge of a rimrock several miles walk from the nearest road........I went on a search for a new rear bag.
I wanted something lighter because although I really liked D Hollands bag, it was really heavy and flopped around a lot while walking if I had it clipped to my belt loop or pack belt.
After a lot of searching, I have found nirvana: The Wiebad Mini Tac Pad.
http://wiebad.mybigcommerce.com/mini-tac-pad/
Its incredibly light and very versatile. Eventually, I cut the straps off it since I'm not shooting matches and won't need to strap it to anything.
I will confess that I absolutely hated it and thought I had wasted my money when I first got it. It looked too big, it was too hard, and I couldn't get it to compress or adjust elevation at all. But I was so ****ed that I had wasted my money I was determined to use the thing! I don't know what the magic number was, but once I had used it X number of times, all of sudden it was absolutely perfect. Now its squishy, holds absolutely rock solid when you squeeze it and its still light as can be. I have used it as a strong side support on my knee when shooting seated also.
I bought the similar bag from SAP (SAP Lightweight bag) for my wife because its a little smaller for her hands and the same 'break-in' period was needed.
You wouldn't go wrong with either choice in my opinion.