At your stage of the game and choosing between those 2, I'd say go with the DX7 and be sure to use an adequate RX battery for whatever plane you put it in. The 9303 and DX7 COULD have the same battery issues if they are allowed to, that's up to YOU to control. Down the line you can buy a 9303 TX and still use your existing receivers so it will be a relatively small cost. Install a properly sized battery pack and monitor it prior to each flight.