Dark looking doesn't mean dark tasting. You'd have to compare the FW/MBV RY4 flavor by itself, vs many other RY4's to see what I meant.
What I mean is, most RY4's are generally light to medium
tobacco with a medium to heavy vanilla/caramel, the MBV/FW one is nothing like all those other RY4's it's a odd/different spicy
tobacco with dark caramel/licorice-like notes with little to no vanilla
Since that is the only RY4 you've had, sorry for confusing you then, you'll have to try others sometime if you want to see/taste what I meant
Basically, it's an "oddball" in the world of RY4, most if not all RY4 fans would not consider it a mainstream RY4 at all.