I've been cutting down nicotine now I'm dripping and using a tank. I DIY mostly but like to get a bottle of pre-made just for fun at times. When I was using an e-pen I was using 18 strength and would probably be looking for that as a new vaper, but as I chain vape that reduced to 12 which I mixed myself. What I will be settling for now will be 6 using a dripper/tank. Using the pen as a new vaper I would be most likely to buy an 18 strength 10ml bottle, but now a 6 strength 30ml bottle if I was a regular customer. 3 strength is ok for me just to try it out, as I can get a higher strength from other liquid if I feel like it.