I am not familiar with the Air Boss from Herr (now Sig too) but I know that Herr has put out some very nice 1/2A aircraft. I am familiar with the Rascal. It is a beautiful airplane, you choose the color, and it does come with motor and ESC. It comes both as a kit and ARF. I don't know if the kit includes motor and ESC. I know that the ARF is very well done and flys very well. It is a very simple airplane to build and you can cut a bit of weight if you build it yourself. Just trim out a few lightning holes a bit. As the ARF comes it is not very heavy in the first place. making it lighter as a kit may not be necessary.
As to the radio, I have a Hitec Flash 4 FM and it is served me well. If you can swing it try to get the 6 channel Flash. I believe you can buy the Xmitter alone from Hobby Horse in Wisconsin and then you can buy a flight pack witha 555 RX and HS55 or HS81 servos. If you chose the Rascal I would recommend he HS81's. The flight packs run around $65 plus another $10 for the Xtal to match your Xmitter. The 6 channel will give you room to grow as time goes on. As to themotors I don't know what is appropriate for the Air Boss but the Rascal requires a geared 400.