RE: A radio to grow with
While all the radios mentioned are very good radios, I did notice one glaring ommision - The Polk's Tracker radios.
They are 8 channel radios that can be used with ANY receiver on ANY channel.
The radio comes with a Seeker receiver (can use on any channel with any transmitter) 900 mah batteries (most radios only have 600 mah batteries) and one servo. Yes, you will need to add 3 more servos (at about $8 - 10 each for standard servos), however the TX, RX, batteries, one servo and a 5 YEAR WARRANTY (compared to 2 or 3 year for other makes) for $200 (about $230 with 4 servos ) is an excellent price.
I would put the radio in the mid range for features/performance, but with only a slightly higher price than many "starter/1st" radios.
I am not affiliated with Polk's in any manner except as a very satisfied customer.