In my completely unproveable opinion after years of loading both plain brass and nickle brass I find plain brass easier to work with. I however never toss a case based on its being nickle. I just keep using them until they fail usually with neck splits. I know I have some 45ACP cases from the 50's that just keep on going. I do not buy nickle cases any longer because I do not personally see a benefit warranting the extra cost.
Over the years I think I see a lot of quality variation in brass quality from all manufacturers. Why I have no idea but it seems sometimes the annealing process is sloppy or maybe the bulk supplier of brass did not get the alloy correct. Just load and shoot and toss the bad ones or occassionally toss the bad batch after compaining to the supplier.