To give you an idea what the view of the field is like from section 20, here is a Youtube video shot from there during a Rangers/Detroit Tigers game at Rangers Ballpark.
One of the best seats I have ever sat in. Great views of the entire ballpark and your so close to the field its unbelievable. You can see every video board perfectly. I wouldn't say there is any down side to these seats besides just being aware of line drives and broken bats.
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