My daughter used glass bottles. I loved them. They are extremely easy to clean. Plastic bottles tend to be hard to clean but as the others said when they hold there bottle it was a little scary. It was also hard for my daughter to hold her bottle at first because it was a little heavy. Overall I loved it but its what you prefer with your baby :)
Yeah I agree I wouldn't use them once the baby holds them
Well they are safe until your baby starts holding their own bottle. But glass are supposed to be very good