I don't know about this exchange but it seems like they copied Binance in looks, but the website interface doesn't look as sharp as I would expect. I have not even heard of this ProperSix exchange before , maybe it's a local exchange in Estonia? Because below it's written that it's licensed in Estonia, though it doesn't really have somethings I would really consider for an exchange.

Moreover I am not going to take your word because you do have any reputation gained among this community. There are already exchanges we know that are far much better and convenient to continue. When are no enough reasons, you must create some promotions so that people may think about checking your recommendation.