MT4 and MT5 don't handle orders the same way, and strategies notice

[Shadow Trader]

Plenty of scalpers still run MT4 out of habit. MT5 has been around for years, and the differences go well beyond the look of the platform.

Order types differ. MT5 offers more pending order types, including stop-limit orders, and handles partial fills as a normal part of its design. MT4 has a simpler order model with fewer ways to go wrong, and fewer ways to express intent.

Account modes differ. MT4 is hedging only. MT5 can be netting or hedging, depending on the broker's setup, which changes how positions are tracked.

The way history and ticks are stored differs too. MT5's strategy tester can use real tick data, if the broker supplies it, and offers multi-currency testing. MT4's tester relies on modelled ticks built from minute bars, which is a weakness for scalping research.

Execution behaviour sometimes differs on the same broker. Two platforms connect to different servers or gateways, and fill speeds can vary. Anecdotally, some traders find MT5 slower on certain brokers and faster on others.

Code is not portable. MQL4 and MQL5 are different enough that an EA needs a real rewrite, not a recompile.

For research, MT5's better tick handling is a strong argument. For live trading, the real test is fill speed on the actual account.

Which platform has delivered the better fills for scalping, and was that measured or felt?