Quick list of tips to make a blu work nicely:
1. buy better liquid. The liquid in blu's carts tastes nice, but doesn't work well in my experience. I have had good success with Johnson Creek, ECOpure from Intellicig (available from InnoVapor and others), and most recently, Decadent Vapours, my new favorite. If you want more vapor, use liquids with a high vegetable glycerine (VG) content.
2. Refill carts. Use a straightened paper clip to poke
through the hole in a blu cart's mouthpiece and push out the transparent inner cart. Remove all the plastic and foil from the lip. Pull out the filler, rinse it, dry it, and push it back in, and refill the cart (not too full) with the better liquid you're using because you're following tip #1. Bonus: replace the stock filler with something that wicks better, like Fluval or (my favorite) PET from Lipton Pyramid tea bags. Other bonus: replace blu's carts entirely with 306a carts, which work with blu atomizers and
batteries and are, despite one leaking incident, currently making me very, very happy.
3. Learn to pull. The blu has a very light draw. Pull slowly and carefully, and give the blu's atomizer time to vaporize the liquid and add it to your air intake. If you're doing it right, you'll actually hear the liquid sizzling as it's vaporized. If you want to tighten up the draw, use a thick liquid (such as ECOpure), and you can also cover one or more of the four air intake holes (right where the battery meets the atomizer) with your fingers.
Please note that yes, these are hoops to jump through, but they are more or less the same hoops people jump through for other models of e-cig-- buying liquids, refilling carts, etc. Crazy as it sounds to most, I am actually far more satisfied overall with my modded blu than I am with my 510-- the 510 puts out great vapor and throat hit, but I find it too big, too clumsy to use all day, and generally too inconvenient, and it seems to mess with my flavors a lot, too. I leave the house in the morning with a loaded blu pack (one e-cig ready to go, five extra differently-flavored carts with atomizers attached, and an extra blu battery) and I'm set for the day.