MT5 is the newest language and does have some advantages. I like to build and fast back test on MT5 myself using the generator, but its very liimited. I cant program in MT4 so I have to hire it out. Hiring out a MT5 build is more expensive because so few people are expert programmers in MT5. Also, many forex brokers use MT4 and very few brokers are using MT5 at this time.
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