Poloniex, bittrex, btc38 are biggest altcoin exchanges. You can trade/invest altcoins there, good luck.
btc38

Haven't heard of this one.
Is there any evidence that they are okay to use and invest? If less than a year old exchange I would skeptical to use them due to the recent developments with the well known exchanges.
Same here never heard that site and looks like this is new.. so better to dont invest large amount there so that you can not lose if that site will be gone.. always use well know site.