People often site the weight penalty on Ortliebs...but I just don't see it. Nashbar says their front water proof panniers are 2 lbs 6 ozs (38 ozs) for a capacity of 1056 cu in. Ortlieb says their fronts are 46.2 ozs for a capacity of 1526 inches. 50% larger for 8 ounces.
Nashbar didn't give a weight on their non-waterproof so I can't make a comparison directly to that.
You have more of a point on the Surly Nice racks But I don't think the difference is overwhelming. Surly says the weight on the Nice rear is 2.45 lbs (40 ozs) with all hardware and bolts. Tubus gives the weight of the Cargo as 22 ozs (which may not include hardware and bolts). So the difference is probablly about 1pound.