More reliable backtesting is on MT5.Some coders are converting their EAs from MT4 to MT5 versions just to optimize and to find good settings.Besides, MT5 is having the option to backtest with the 'real ticks' - it means that backtesting will be same as the trading by EA on same broker's data for example.
More information is below -
Forum on trading, automated trading systems and testing trading strategies
PriceChannel Parabolic system
Sergey Golubev, 2017.02.15 06:02
You can read this article (TESTING TRADING STRATEGIES ON REAL TICKS).
-------------------Just an example - MT4 and very old builds of MT5: I optimized the EAs from this thread just to find good settings for the pair, I was backtesting them, and I traded on demo for some time just to be sure that EAs are profitable.With new builds of MT5: I will optimize the EAs from this thread to find the settings, and I will backtesting them with 'every tick based on real ticks' - and it will be same as trading by those EA on real account for many months or years!
MT4 & MT5 backtest
Sergey Golubev, 2017.02.17 20:53
If you are backtesting EA on MT5 using 'every tick based on real ticks' so it will be almost same with trading on MT5 platform with some particular broker (because it is based on actual historical data).
Example, read this thread: Why is it better MT5 than MT4?? Does it have fewer limitations ??? - this is the quote from the first post of the thread:
For more information about it - read this summary.
As i know - some coders/traders are converting their MT4 EAs to MT5 just to backtest them and/or to find the settings with optimization to get the backtesting results that are closest to reality.
All (not yet) about Strategy Tester, Optimization and Cloud
Sergey Golubev, 2017.07.22 07:31
Testing trading strategies on real ticks
The article provides the results of testing a simple trading strategy in three modes: "1 minute OHLC" using only Open, High, Low and Close prices of minute bars; detailed modeling in "Every tick" mode, as well as the most accurate "Every tick based on real ticks" mode applying actual historical data.
Comparing the results allows us to assess the quality in various modes, as well as helps us to use the tester more efficiently in order to receive results faster. "1 minute OHLC" mode allows receiving quick estimated test results, "Every tick" mode is closer to reality, while testing on real ticks is most accurate but time-consuming. Keep in mind that errors in a trading robot's logic may affect the number of trading operations making the strategy test results more susceptible to a selected test mode.
Sergey Golubev, 2018.01.06 08:51
Good thread was started -
MT4 Strategy Tester : good practices, know-how and howtos
This topic is NOT to ask questions, it will be used as a reference.