RE: What O.S Engine to get ?
Avistar 2, IMHO leave the LA series alone unless you just absolutely can't afford better. The Voyger deserves a better engine than an LA. You can always throttle back, thats what the left stick is for. A TT46 PRO or an OS46 AX or older FX would be a great match.
$120 for a radio?? What radio?? We need more info.
Fred