Yeah - I'm definitely not a FW expert. I have a handful or two of theirs and I remember reading the 10-15% recommendation on ecig forums a lot when I started with them. Personally, I've never used any of mine higher than 8 or 9% and that was for butter pecan flavor solo. (Which seemed perfect, to me, plenty strong). It's always prudent to start low until you get to know a flavor.