None of them, the cannabis industry doesn't need them. However potcoin seems the most promising since it has a good team pushing hard to get the coin out. Potcoin and Cannabiscoin seem the most promising but I'd rather invest my money into something else.
The Cannabis industry has quality control, banking and legalization issues for something that can greatly help human health more than traditional medicine, and it can all be significantly improved upon in the blockchain, so for people that care about that it is important to support these projects. They have a good team, but so do the other projects pushing hard including ours.
https://bitcointalk.org/index.php?topic=2112470.msg21120617#msg21120617As long as FDA keeps marijuana illegal they'll be making millions from shit drugs, reality is marijuana can cure 100+ diseases and they don't want that. Imagine if everyone in the world started using Rick Simpson oil for cancer, the government will stop making billions off of chemo and medications for cancer alone.