Since Attack & Release, their actual "studio" stuff became much more polished because they were working with Danger Mouse as their producer. Subsequent albums became better quality, but are kind of of a type of music that really doesn't lead itself to too much polishing. On that note, Brothers was self produced in studio so it sounds a bit rougher than El Camino, which got Danger Mouse back producing. They're both great albums, just not really audiophile quality. I own their entire catalog and find them much more at home on my 1200mkii than on my Scout but still play it through my Rogue Tubes and Vandersteens. I don't find that it's anything I'd do any critical listening to. I'm pretty sure they weren't pressed immaculately either though you can find them on 180g.
Hope that helps.
Hope that helps.