One item I was very interested in at the IDE was the ITELITE DBS Long Range Antenna (model DBS-03-ver.2) for the Solo. (See http://www.itelite.net/drone/ )
I procured one recently and tested just last weekend. Its certainly does what it says. The pics show the antenna, how to affix to the Solo Controller, and how to arrange the waveguides so you dont kink or catch them on something.
I posted a couple videos on my YouTube channel showing the test results. I'm out to 1600 feet or so, and the signal strength still showed "two bars", but I forgot what I heard the Tower app say my signal strength was in dB. I'll bring a witness next test flight.
The signal WILL QUICKLY ATTENUATE when you try and control the Solo when its being obstructed by tall PINE trees. Those long needles can scatter the signal (likely the transmit from the Solo).
Looks like a small cell antenna. Made in Poland (well, the former German city of Breslau now Wroclaw). Good investmnent for $109.