Myetherwallet is best for ethereum, it is support for erc20 token mean can be used for participate in the ICOs projects, no need download all of the ethereum's blockchain, myetherwallet is secure too just becareful with phishing website of myetherwallet, it will be dangerous for our ethereum and our token.
yes that's a very horrible case, many people lose their coins there.
I suggest to avoid slack, and always check on MEW address. or bookmarks your MEW so fishing can be avoided.