Id' say both only because they're both bad. Marijuana might not have any effects that they've noted, but the fact that it is so detremental to the smokers health (mainly because where and how it's processed these days means there's LOTS of crap in it) would make me worry. I know someone who has had severe mental problems because of pot and pot alone. Scary stuff. Alcohol would be ok in small amounts (JMO) but definitely not binge drinking often or anything like that.
xo