You sound like you filled them fine. Without a syringe (which you don't have to have) you could do the condom method to get a little more juice lower in the carto. Put about 10 drops or so in the rubber end cap and slowly push the battery end down into the juice. It will slowly push juice into the carto from the bottom up.
So, how do you like it?
I'm not sure about the cartos. Hopefully someone else here will be able to ID them for you.
Honestly there is more of a hit from these than I thought there would be. The first time I drew on it I thought I was taking it slow but I coughed it back out. It tickled my throat, and actually gave me a buzz after about 5 hits on it.
I don't know what that buzz was from for sure. It could be the nicotine, but I already smoke and have nicotine in my bloodstream. It could be PG or VG that im not use to inhaling. But its actually harder to inhale than I thought it would be. Almost like when I first started smoking without the lingering taste and bad health effects of course.
My verdict isn't out yet on these as far as whether or not they deliver nicotine or will help me quit. I should know that with confidence within a couple months of use. I just have some adjusting to do, I have to find the cartos I like and juices I like
Functionality of the roughtack is great so far, it works like it's supposed to.