Heh heh, so these guys say what I say but recommend you buy crap.
Here's what my paranoid ass did a year ago when I had to pass a test: I hit the fuckin library and read about piss. Kudos to the folks in your link for giving good info, but you STILL don't need to buy shit that's marketed to potheads who don't wanna go to the library.
My advice is free nigga; but you can send me some RB cognacs hehehehehe.