I can't say I really "trust" one more than the other, it's just whichever one gets hit first. Having said that, in my line of work (electrical/mechanical), you can often smell and hear problems before you see them.
Sight. Although I suffer from astigmatism, I still trust what I can see with my own two eyes more so than not. Also, when I'm learning a new activity or skill, I learn best by watching the first time, and then doing it myself.