Just got 2 boxes of smok tech DC cartos, 1 pack clear 1 pack stainless. I syringe filled bottom to top, rotating 4 times, NO LEAKS on my first try just by reading about this method. They sure do cackle but I think I'm gonna hafta knock down my nic level to 10mg or so... the vapor production doesn't LOOK bigger but the taste and nic hit are so intense! I'm going through old flavors I didn't care for on joye 510lr attys and am blown away! +10 for these DC's if they last as long as I've heard, but my initial "out of the box" impression has me regretting ordering the 10 LR attys with them lol, 46$ for 10 is hardly a bad investment from vaporkings but ... just wow at these DC's. Wow. If these last a week a piece, they're a godsend.
EDIT: Using them exclusively on eGo batteries, 650mah - 900mah and the usb passthrough. All golden so far.