OK I regularily use power service as I'm up in cold Canada and worry about gelling in the winter months but after reading so many threads here about people gelling up or clogging filters with additives I'm at a loss as to whether the additives are worth it / needed. Yes I understand the lubricity studies and such show gains but does that really justify additives. I guess I'll keep with the train of thought that it's cheap insurance but I've talked to so many old school farmers and oil patch guys who don't, and have never used additives and don't have problems (in -30C). I personally don't put much weight on the manufacturers suggestion that additives are not required... is it truely a fuel quality issue, or a build up of condensation over time with less than full tanks? I'd guess 50% would say use them and the other 50% no.