Are you looking for a bitcoin wallet where you can save your bitcoins?
I just checked the Quadrigacx which is just like a bitcoin exchanged site so you are looking for a exchange site?
If you really want to be safe of your bitcoin better to choose the well known wallet which is good to use look for electrum wallet i am using it from 2 years ago and until now its working fine never had any problem..
Or if you are looking for exchange site you can use poloniex instead but its not safe to save bitcoins for a long time in exchange site or web wallet because there are some exchange crash and hack and you don't have any control for your bitcoin wallet.. so electrum is the best choice because you can backup the private keys that you can use to recover your wallet in other wallet..