The demo trading can be effective for any kinds of traders who are especially beginners. Besides beginners it would be a great place for the regular traders, before live trading if we can use all trading strategies first of all in our demo account to see the performance how it works. I think it will help us for avoiding loss with certainly.
A demo account is good to practicing and learning process, when traders learn about a certain trading system, or they find new expert advisors, using a demo account is free without any risk to review trading performance on specific trading system or expert advisors. You can try to use the demo ECN FXOpen broker to learn to trade.
I mostly trade with USDJPY and EURNZD-great liquidity and spreads on them. But sometimes news can lead to me opening trades on USDINR or AUDJPY-when I can be confident enough.