This may be a subjective topic with litle bit, but here is some information that may help you decide:
IntelliJ has two main predefined keyboard layouts for OS X (you can find them in the Settings / Keyboard Layout section).
The Mac OS X keyboard is similar to the Linux / Windows keyboard. Therefore, if you need to switch between multiple systems, this is probably best for you.
The Mac OS X 10.5+ keyboard is designed to be installed in the OS X ecosystem, so if you are used to the common OS X shortcuts, it will look more natural and you can easily guess a lot of shortcuts.
Below is the link for Mac OS X 10.5+ .
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