The quality of a broker can only be tested in practice. First, you can try to work on a demo to evaluate the terminal and its speed, the number of assets and indicators. Secondly, you can work with small real capital to see how the broker reacts to your profit. Third, you can try to withdraw all the money you have in your account. If the broker doesn't create any problems, that's fine, you can work with bigger capital. If you get suspicious, you better not take any chances and find a better company.