William has mentioned it's not possible to backtest this system, which as far as I understand is because it gets its trading signals from a server. So this myfxbook account is probably the only historical data we can go from.
Oh, I didn't even know that was possible :) At the very least, it looks like a very professionally made piece of software. Now I'm of course just eager to see how the trading will go on my own account! Only time will tell :)