Just received my Striking 10th last night. I can assure the "legibility at a glance" is no problem. I had a metal handed Speedmaster 3507 and could not read the time, it was so bad I had to change out the stock metal stick hands for broad arrow hands which improved the legibility a huge amount but can sometimes still be a problem when dark. I can say the El Primero is really good - really easy to read at a glance. Not as good as the Rolex Polar Explorer 2 42mm (you can read that from across the room) which I flipped for the Zenith but pretty close as to make it a non-issue. You can see below, the broad arrows are still a little hard to read. The hands on the Zenith contrast with the dial - so they stand out.
