Ortlieb now also do a budget line, the City Line, that are basically Classic rollers without some of the frills, and as a result they are a quarter cheaper and a quarter lighter, but of the same rugged quality. Weight 1520 grams. I have written to Ortlieb to encourage them to offer this type but with the lighter material of their Plus series. If they were to do that the rear panniers would be something like 1300 grams. If you feel the same as I do, just write to them and who knows they might just discover that there is a market for lighter gear.
To be honest these POE panniers are not so much lighter than the Ortlieb City line that I would risk unreliability. Panniers take a hell of a beating at times.
The Polish company Crosso do even lighter ones, but I really have no information on the quality.