maybe i just got lucky, but has anyone else noticed the usb unit's switch is many times better than any battery? mine works with slightest draw, and has never "stuck" on, and gives tons of vapor(tried with different atomizers).smokes just like a dang cigarette.... why the heck cant the batteries be this good?, or have i just not gotten a "good" one?...i have 4 batteries.curious of others' opinions on this....