There isn't much difference between these 2 expressions, they are interchangeable

There isn't much of a difference between the two sentences, they essentially mean the same thing. Just depends on how you want to say it.

"for example" can be used with a hypothetical. "for instance" can't be. Otherwise, you could use either, but "for example" is much more common.

They are the same, for instance is slightly more formal and used less frequently.