I've used PBW, OxiClean, and Sun (in decreasing order of cost). I've had good results with all three.
Recently, OxiClean switched their packaging from a round container to a rectangular container, and I've had some problems with kegged beers cleaned with the new OxiClean. After a week or so in the keg, I am noticing a slight sour taste to the beer, and some sediment in the bottom of the glass. This has never happened before, but it has happened in each of my last 5 batches. I don't think it has anything to do with the OxiClean, because I use that to clean my primary as well, and everything seems fine until after it has been in the keg for a week or so.
Has anybody else had a similar problem with OxiClean in the rectangular container?
-a.