Okay, just a follow-up to this. For anyone new to this, there has been a perennial problem with chemical off-tastes to water in MSR Dromedary bags. Read back up this thread to learn what I did.
My bags also act as part of my emergency kit, so I fill them up and change the water out about every 6 months. Yesterday, I tasted the 6 month old water in all 4 of them and it was clean with no off-tastes. So, if you were waiting for me to report back, here it is 4 years later!!