Let's just clarify something about *demo* accounts. Demo accounts are just as customizable just like any other type of account the broker provide. That means, spreads, slippage, requotes, execution types, SL blocks etc etc, are all customizable. A decent broker try to match their demo accounts with their real accounts. A bad broker will show you great trading conditions on the demo accounts while all kind of shit happening on the real accounts. Hell, they could have a completely different data feed. Now, that is also interesting, because no matter how close they may try to match the adjustable parameters, the fact is that demo servers are rarely prioritized for latency and performance, for cost reasons. (Especially true for new or small brokers.) What that means is that, the slippage (due to latency) and requotes may actually be greater on demo accounts.
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