They say with "legal highs" (like fake cocaine and ecstacy and stuff) its actually SAFER to get the ILLEGAL one coz that way if anything happens to you they more-or-less know what chemicals are in it and how to counteract them...hell, think about the "bath salts" coke stuff - theres some wierd chemicals in it which COULD cause or react to dangerous allergies unheard of in the person before...
But legal WEED - again, I dunno whats in it so y'know...at least if its PROPER weed I know what I'm getting