Sams club had the cheapest i knew of. If you sing up online for the monster army you get 35% off, but im not sure if thats on the drink or clothes though.
the only one that actually works for me anymore is spike. i'm immune to most of them, but spike is pretty wicked. my hair was tingling first time i drank a can.
Amp is yummy ... I also like Full Throttle as well ...
Personally, I can't stand Monster ... Tastes like someone ground up a bunch of rockets and mixed them in carbonated water ... //content.invisioncic.com/y282845/emoticons/sick.gif.b1847c8dabbfeeddbcf1a78052249e10.gif