I Love the 510s as well. I have a bunch of the new short manual batts with the led and am only getting an hour or so use out of a charge. Atty got wimpy after about 5 days, gave it a good cleaning and is now drying. Tried a new one and it kept giving me a burnt metallic taste. Nope it wasn't the cart. It did this even when I dripped with no cart filler. I broke out another atty and all was fine. I may try and give that bad tasting new one a cleaning and see if that helps. Not sure if it is some kind of contaminate or bad primer fluid, or what it is. I have had this once before with a brand new 401 atty. It eventually got better. I really want to stock up more on 510 attys, I have just spent too much money on E-cigs in the past few months. I suppose I am going to be ok for awhile counting all the 901s 801s 401s and 510s I currently have. Sorry, I don't have an acurate count, I have cigar boxes full of them.