http://www.airventure.org/news/2013/130731_transponder-tech-getting-to-2020.html
good to see more options coming for ADS-B out compliance.
a very pleasant surprise for me is the Bendix King KT-74 option. not only lower priced than other Mode S with ES but also a slide in replacement for the KT-76 will make it very attractive for KT-76 equipped aircrafts and there are lots of them !!
which brings up the following question: why does Garmin wants us to rewire when slide in replacement can be an option ?