I think it's cover the brake. In any case hitting the horn did not seem to do your 'T' bone case much good.
The horn is a reaction-thing that happens when 'spidey sense' tells me somthing is up - that' all. The brake or gas is what you tend to cover first, but every accident I have either witnessed or any close call I have had has been preceeded - in most cases - by the sound of a horn.
Now - back to the Sonata - we are at 22500km, and other than a couple of minor fit and finish things it is still performing flawlessly. BTW - does anyone have any suggestions about reducing the little rubbing sound that you sometimes hear from a sunroof that is closed? I was wondering, for example if a wipe of armor-all or something like that would be in order?