Dave,
If you ask Ed (the guy who makes them) there has only ever been one model, hence Mark's Horns are current, plus his offer you the advantage hearing them with the FE 108. There are still some people who are of the opinion that it is a better driver than the 126.
Having the binding posts mounted up top is another advantage as your speaker cables practically attach to the driver. This allows for a neat little mod Ed let me in on where you sever the leads to the binding posts inside and route them through the cabinet by drilling some pin holes just behind the posts so you can thus "clamp" your speaker leads directly to your speaker cables via the posts instead of passing the signal through them. Believe it or not this little trick makes them a notch better.