Better to use collision or overlap?

Is there much difference between the collision and overlap conditions? Just wondering in case 1 of them is more efficient or something. Is the collision trigger checked every tick? Whereas with an overlap condition, I have more control as I can use it as a 3rd condition or a subevent, so the overlap is only checked when I need it to be. But if collision is a very efficient/simple/non-intensive condition then it doesn't matter which one I use?

The main difference are that collision is a trigger and overlap isn't.

Thus collision is an instant condition, it's true the first tick where the object start overlapping, and then false.

But! It's a trigger. So it's not exactly the same as doing

Object: is overlapping
System: trigger once

Actually, in the SDK, 'On collision' is a "fake trigger", meaning it's treated in the editor like a trigger but coded like an ordinary condition!

'On collision' is therefore treated almost exactly like:

+ Is overlapping

+ Trigger once

'Is overlapping' actually does looping over the affected instances which is not usually noticable, but that behavior should be removed from a future build anyway since it is inconvenient in some situations.