I use Northern and have had zero problems. I full time and not one issue in almost 4 years. I do use a lot of water however. When boondocking paper doesn't go in the black tank, it goes into a trash can with a liner that is thrown out frequently.
2006 GMC 2500HD CCSB 4x4 Duramax/Allison, Titan 52 gallon fuel tank, Prodigy Controller, B&W Companion Hitch
2010 Jayco Designer 35RLTS, Cummins/Onan RV QG 5500 EVAP, Progressive Industries EMS-PT50C, TST Systems 507 TPMS, RV Flex Armor Roof