woofer orientation

[JoeA4]

Is it better to mount a woofer horizontal; you can look right into the face of the speaker? Or vertica; like it's sitting on a table with the cone facing the sky? I am asking this in regards to long life of the speaker's internal working componets.

[BIZILL]

i was reading something recently that certain subs are purpose-built for horizontal placement (cone facing down) as they are subject to the effects of gravity and 'sagging'. i think it's sort of negligable. vertical mounting (forward-facing) is impervious to those forces.

...just based on what i read while researching...