Always go for the side window, ideally a lower corner at just a few inches from the window’s frame. This is the safest spot to work, but in an emergency, you might not have optimum conditions, so you’ll have to do what you need to do to escape. You don’t want to attempt breaking the windshield;because that tempered glass is laminated with a thin plastic sandwiched between two sheets of glass. The plastic layer holds the glass in place, making it much harder to break through, possibly thwarting your attempt to escape.