Playing with Sub ohming is actually the first time I realized this. I always did 12mg on a standard 1.8 coil at around 12W, but as satachvai says that really is too much for higher wattage. It straight up kicked my ....
So I had to go down to 6mg which killed my favorite (Space Jam Eclipse.) It just tasted wrong at 6mg compared to 12mg. The 3mg? Don't even get my started
But then there are other flavors that I've bought and didn't like at 12mg, where they had too much kick- but now love at 6mg. So it really does seem case by case. I can almost tell based on the bottle, and who they are marketing to, what Nic level it's intended for. Most seem to be geared toward 6mg or 3mg lately, and they actually taste better at that.
I'm actually trying to cut down to 6 Nic going forward, regardless of wattage but it's like starting from scratch in a way. I would definitely try your guabana at a 6 though and see how it feels/tastes. If you ever find you're getting the jitters the 12 may be why depending on how high your Wattage is. 12Nic at anything more than about 15 Watts makes me feel funny.