I can't buy Dumor unless I am in a desperate situation. I bought one bag of starter once and it was okay, though it didn't smell as good as Tucker Milling. Then, the second one was green. Yuck, took it back. I knew they had a rep for bad feed, per Ladyhawk's terrible history with moldy TSC feeds, and I guess it's well-earned, at least at some locations.
Mine actually like the DuMor, which is good, and I haven't had a problem with it yet. Purina actually makes it, so it's almost pretty much Purina branded for TSC, although there are probably some differences in ingredient ratios.
I'm glad DuMor is working out well for me because everything else I have access to is at least $2 more a bag around here - no local feed mills or anything. The closest one is over an hour away.