Both work for me, though https is slower and won't embed videos. And I recall from when I used it before here that it tended to throw off error messages (I can't remember what they said) in threads heavy with upload links.
But I have a more basic question, as I am not quite sure what "forcing" https means. Some of us have tons of links in our posts to other threads on site and the Wiki, using http addresses. What would forcing https do to these links?