You can always count on Cyclic Hardover for valuable insight.

The Sig LT ARF is a great little trainer and would give you the opportunity to pick your own engine and radio.
I've trained students on each of the other 3 as well and each has it's own qualities.
The 2 Hangar 9 products come with JR Quatro radios and the Avistar with the Futaba V4F radio. These are all VERY basic entry level radios that you MAY outgrow quickly. For just a few dollars more you could have better radio systems in either plane. Just something to think about. The Avistar is a bit "zippier" and better as a second plane but with a good instructor and good training can be a first plane too.