Before you buy a night scalper please be aware of the risks involved:

1) Past performance is no guarantee of future profitability (the EA could also make losses). 

2) The backtests shown (e.g. in screenshots) are highly optimized to find the best parameters but therefore do not give a realistic prediction of future profitability.

3) Any mean reversion can get caught on the wrong side of a fast movements due to unexpected news or flash crashes. This strategy will always use a stop loss, but still execution of the SL depends on your broker.

4) Night scalpers are dependent on good brokerage conditions, like low spread and slippage, which might be worse on high lot sizes.