Quick Recessed lighting placement question

[RickM]

Just curious if there's a standard distance (or range) from the wall when installing Hi-Hats.

On 6" cans I typically place them 10"-15", wall to center. I take into account placement, overall aesthetics and symmetry. However, the joists don't always cooperate. I also try to consider future furniture rearranging...just to make things complicated.

What do ya'll have to say?