New to forum, but I did research about the most popular flavor being bought in the USA. I'll spare you the jargan and just get down to it. Juicy Fruit is the absolute top dog as far as sales go (in the USA). That particular flavor sells the best... unfortunately, I'm not a huge fan of it so its rather irrelevant for me to say "yay" or "nay". There are dozens of vendors who sell the flavor so it's highly "available".
One vendor that I absolutely trust and use exclusively now is Mt Baker Vapor. I live in Oregon and they are based in Washington. That, actually, has nothing to do with it though. Their e-juice prices are just insanely cheap. They have tons of flavors and even a "build and name your own" feature on their website. Occasionally you may need to steep the juices but usually they arrive ready to vape. I can't say enough good things about them. I have tried, literally, dozens of ejuice manufacturers (foreign and domestic) and Mt Baker Vapor are the most reliable, consistent and cheapest I have found.
My preference = 12-18mg nic, 20% PG and 80%VG
I use Vision Spinner 1300 mah with Vision Clearomizer V2
I will say this... Flavors, manufacturers, etc., its all subjective.