Yes, Copperhead and MEL's RY4 are both very good. From their tobaccos, I also personally loved Red Rider and HFC, as well as Casino.. Grey Matter was also a great juice, sort of a sweet dry tobacco. I haven't seen test results for any of them though... the flavors were just great.
Yes, I agree, Jade Tiger or Jade Ice is also a good and unusual flavor. Watermelon, coconut, strawberry, pineapple... mm. (ed. I just noticed there's no such thing as the Ice line anymore. You'd just order Jade Tiger and "add ice" (menthol) if that's what you like. I did love Jade Ice when it was called that.) Paradigm is tasty too if you like Coconut. I also particularly loved the Reverb (dripping line) Dropsicle, but that's not cheap at all. Much more than the other MEL's, but IMO probably worth one bottle if you like that kind of flavor profile... lemon, peach, raspberry.