I just wear a shirt. I agree that a pad isn't as secure... you NEED that bar to be secure when going heavy (even when you're not it still should be). Besides, with a pad on, that means the bar is farther away from your back, and your arms, which are now primarily responsible for holding the bar up, are also farther away from your back. In this position, they have much less strength than they do when they're in line with your back. So would you rather have your back and your arms holding the bar, or some pad and your arms in a disadvantaged position? I'd rather trust my back, one of my strongest body parts.