Just a few more points on the slimmed selections:

Ihave never held or seen a newer Airtronics radio in action, so Ican't really comment on it. However, when the brand is brought up in discussion Ialways hear good things. The model you listed does not offer telemetry if that bothers you.

The DX8 is one of the most comfortable radios Ihave ever held. Idon't care for their switch layout, but the ergonomics are some of the best my hands have ever seen. Spectrum also offers their ModelMatch technology that no one else offers. Its a good way to keep the wrong program from crashing a plane. AIgood preflight check can avoid this all together, but everyone gets distracted as some point. Inever cared for the satalite usage in Spektrum receivers. Its just one more connection that can cause issues. Keep it simple in my opinion. Using the Spektrum system, you are open to all of the BNF options out on the market that Horizon offers. Istill have my DX6i around just to use with these smaller but very fun planes.

The Aurora 9 has built in battery voltage telemetry on their 7 and 9 channel receivers. No other TX/Rx offers that option until you get into the pricier options. Both DX8 and A9 have separate telemetry modules if you go down that road, but having the Rx battery voltage available right from the Rx without a separate module is fantastic and one of the selling points for me. All of the switches on the A9 are changable which really makes your radio feel custom to the way you want to fly. The large backlit touchscreen is a very nice touch when setting up your model. If you fly helis, you will be hard pressed to find anyone that uses a A9. They are not looked very highly upon in the heli scene, even though the A9 offers heli programming. The biggest item that had me concerned about the A9 was the open wire on the back of the radio connecting the Tx module to the radio antenna. Iwas worried about it being a weak point for failure, but Icould not find any complaints where that was a problem. For reference, Hitec designed the A9 to be used as both a 2.4 GHz and a 72 MHz radio, so they left the antenna integration aside for the versatility.

Besides these basic differences, all the radios offer many of the same options so I'm sure you will be happy wherever you land.