I've tried this system and I got 2 wins and 1 loss. I use a risk to reward ratio of 1.3 - 1.5 depending on the trade. So even when I get 50% wrong, I make a profit. I can tell you, this system works actually very good and is very easy to use. I think it's probably good to use the 200 EMA to see the long term trend direction, that way if the EMA is long term bullish, and you get a buy signal from this system, you can easily set the risk to reward to 1.5.
Probably a good idea to only BUY when the EMA is bullish, and only SELL when the EMA is bearish. That way you will increase your winrate.
Timeframe: H1