tricky question really. Better in this case is a bit of personal thing. Most of the standard cd ripping software all do the same job, it's just a case of what bells and whistles you find useful, and which package you find easiest to use. DBpoweramp is very good and very easy to use and also has the AccurateRip facility (which checks against an online database to basically make sure you have the best rip you can).
What one tends to find is that the free software can do most of what the paid software does, but it might not be as near as user friendly (as you found out with CDex) or may not have as many features.
In short, if something like dbpoweramp does what you want, and you like it, and you think it's worth the cash, then I'd say go for it 🙂