Hello, payment systems earn from the commission they receive from each payment, so the size of this commission is an important criterion. Checking how secure the system is is a bit more difficult. To evaluate this parameter, you can check information about it on the Internet. If the reputation of the company is trustworthy, then it is more likely that you can entrust your money to it. Also, pay attention that the payment system would support
ApplePay acquiring, so that you would be able to have customers from other countries.