Buying in bulk: yes and no. Find a good bulk by trying various samples. Buying online, definitely.
The reason why I'm advising against buying in bulk ( 8oz or more ), taking in account how much you smoke ( not very much by any standards ), you'd have to have some sort of storage for it with the right factors of temperature and humidity. Otherwise the baccy would dry up on you and would end up costing you more ( time, effort and waste ) to bring it back to life. I don't smoke a lot, maybe 4 bowls a day and not every day, and I've had stuff go dry on me.
Like herbinedave said, quality makes all the difference. I find the quality stuff to be more "filling", so to speak, hence I'd smoke less.
I stay away from OTC because the added chems make them all taste like various degrees of cigs which for years I tried to get away from and finally succeeded about a year ago ......