You can do martingale 23h a day 90% payout, I heard they can lower you the % of an asset if you do to good on it but apart from that is the only legit binary options broker, also it has bid and ask but if you combine martingale with different shitty brokers, you can avoid loosing for that, I see dukascopy as a really good place to use martingale, also the minimum per trade is 0.05 dollars if you have your account with MXN