So far I've tried Dekang, PinkSpot, and Volcano RY4s. All three are totally different.
My Dekang must have been steeped because it tasted pretty good, better than OK. The Volcano RY4 was mild, almost seemed like it had some chocolate notes in it, and I've been vaping it regularly the last few days. The PinkSpot (RY8), however, is far and above my favorite, very caramel and rich and smooth. Their Swagger flavor is very similar, and delicious.
I'm definately curious to sample new RY4s I come across and my wife laughs that she knows to throw in "a sampler of RY4" when she orders from a new juice vendor. So far I only really get vanilla, caramel, and smoky notes out of any of the above, so it may be my taste buds adjusting, but I really enjoy it.
I had a friend who had no sense of smell due to a congenital issue, and he said the food he loved the most was pizza, because it hit the sweet, sour, salty, and bitter tastebuds. Without smell, his taste broke down into solely those things, and pizza hit them all at once. RY4 is kind of like that, with smoky, caramel, and vanilla flavors. Your brain tends to taste one of the flavors "up front" but it can change throughout the day.