Like the OP I'm outfitting a touring bike and looking at panniers. I've looked at those Ibera's. They get good reviews but that bar doohicky thing on back looks kind of gimicky. However, for one who may do a few weekend overnighters or such a year, as opposed to weeks and months on the road, they may be sufficient. OTOH, I realize you get what you pay for. Not much between that and the Ortliebs $$-wise.
There IS the Arkel's which is slightly less than the Ortliebs and which get good reviews as well.
https://www.adventurecycling.org/cyc...-rear-pannier/
I don't know beans about bike panniers and so rely heavily on reviews and opinions on here. Having said that, usually the "cream rises to the top" and shortly into researching panniers, Ortliebs obviously have few detractors.