I just bought my transmitter, being also a beginner, a Futaba 6XAPS. My first choice was also the 6DA, but I was told by people at the club where I'm going to be flying that it was not worth it, and should simply pay a little bit more for the computer capability. I got the PCM version of the 6XAS actually, and it was 387$CAN before taxes, but I'm pretty sure the FM version is cheaper.

I know you want to stay below 300$, but it's something to think about!