Since you already own this program and like its results, I say go ahead and use it. I experimented a bit with the program, but found other solutions more to my liking.
ConvertX has many competitors these days, and a few of the best are free. The free mpeg2 encoders have gotten so good I have a hard time recommending a commercial product any more. HCenc can stand toe to toe with ProCoder or CCE in its present incarnation, and there are several good gui’s that can make use of it.