Wow, I've heard of cartomizers for the m401 series e-cigarettes, but not these things. You are using these directly on m401 series batteries? Looks like that would be a pretty nice setup, and would certainly look cool on a stainless steel battery. It's been awhile since the last commentary regarding these. How are you folks doing with them now? I was looking to get new batteries anyway, and atomizers to go with them, so it would be great to get these cartomizers instead, and just get the batteries. How would you compare that sort of arrangement, experience-wise, to just using a standard m401 series 3-piece setup, with either standard or XL cartridges, or even with the PTB modded ones (which I currently use)? I love the m401 series, and I'm glad to see all sorts of nice modifications out for them, but I'm sort of surprised by this one, or that I'm even considering going a cartomizer route. I hope to see more info on these specifically for the m401 series. How long do these last on a single refill compared to regular cartridges?