I have had 3 116520 and 5 16520: overall I prefer the earlier Zenith-based Daytona. It has a nicer design, more delicate, in my opinion. You have a varity of different dials, floating Cosmo, inverted 6 to name a few. And it is less bling, more sports watch.
However, I definitely prefer the pusher feeling of the inhouse movement: what a smooth, rifle bolt feeling! Perfect!
Today, I enjoy an A-series 16520 in very nice condition.