Etizolam. Partly because it is almost illegal and therefore soon to be creating a huge number of etiz heads without their usual easy, and next day source making them move onto other similar things.
Also because a lot of naive users, not knowing the dangers of benzo (yes I know it's not strictly a benzo) addiction and getting into something they might have stupidly thought as harmless. And the fact that they sell it in powder form to anyone with 30 quid! SO DANGEROUS!
The Tesco chick is such a buff ting, it's just a shame she didn't nail a load of etizolam before she decided to go cavorting around her local supermarket. lol