When this coins reach huge trading platforms like Poloniex or Bittrex, they will surely patronize this coins so its realy worth investing and keeping this coins until they hit the moon.
I am also waiting for that update If they can work with other big exchanges. It will be a good because you can now buy and trade their coin freely. You can also store it for future purposes.
You are right, they will become popular if the coin will be listed in large exchanges. But it needs to have a lot of budget because listed in those exchanges is really expensive.