We use agile at my company w/ about 15 employees. We introduced it about two years ago to help focus our development process. Although I know there are some issues with agile, we've fully embraced agile by modifying our process along the way to suit our style. It has worked really well and I wouldn't change it for anything else right now. Does it produce high quality software? I agree that depends on the engineers, but it does produce a predictable process that we all are on board with. That's huge in my eyes.