I'm split on NEX! I think a DEX on NEO is a great idea to be sure, but I haven't done my research yet to find out if it will allow for non-NEO tokens to be traded also. If it's just going to be Etherdelta-for-NEO then I am not so sure how big it will be as NEP5 tokens are still far and in between. NEO itself I am very bullish on however