Smoking too much K2?

Last week's conversation on The Exponent's Facebook page about drunk driving spurred a lot of questions about synthetic cannabis. Synthetic cannabis, often known by the brand name "K2" is a designer drug which uses synthetic cannabinoids to mimic the effects of marijuana. K2 does not show up on drug tests for THC, the active material in marijuana. Because it is made up of a number of different cannabinoids and is produced in a laboratory, K2 (and other similar brand name drugs) are not illegal. It is sold legally in Irish Hills area convenience stores and gas stations. Do you think drugs like K2 should be illegal?