Over my one year of vaping, I've purchased 30 bottles of juice from BackwoodsBrew, 17 bottles from CopperCreek, and 15 bottles from KickBass.
These are great vendors with large numbers of loyal and occasionally even fanatical fans on ECF.
I did tire of the cedar tone in many of Don's BWB tobacco flavors, but his coffee flavors (which I initially tended to ignore in my juice stash) picked up the slack. KickBass is highly praised for their sweet juices, but I'm not very fond of their tobaccos. CopperCreek is all over the map for me. I love some of their juices and don't much like others. None of this is meant as criticism, however. Of the three, BWB would be my preferred choice (if I had to choose), followed by CC and then KBV.
Especially since all three vendors are so popular, the only realistic (and affordable) way to know if you'll like their juices is to buy small bottles of a bunch of their flavors and see what you think.