Perhaps I haven't been breeding them long enough to really make a determination, but frankly at this point I don't see any positive reason to favor breeding natal rats over mice or domestic rats. Sure the lack of a strong smell is nice, but they certainly are not odorless, and the lack of smell doesn't really make up for the numerous negative factors.
Pro -
1. No strong urine or feces smell
2. adults grow larger than mice
3. Allegedly they produce larger litters, a fact not borne out as of yet
Con -
1. overall bad temperament. They bite. a lot.
2. They do not allow handling, no fear of falling so they jump out of your hands from heights unlike mice and rats
3. Growth rate is as slow as mice, they take too long to grow to a decent size
4. They seem to start breeding at a later age than mice
5 while at early ages they are the same size as mice and grow at the same rate, they require much more space than mice. Space that would be more productive growing more mice.
6. Murky legal status. There is a CDC ruling about "African rodents", that may apply to natal rats, making them illegal to own or sell anywhere in the United States.
At this point I'm planning on letting them breed and grow until I have at least covered my initial outlay. I guess somewhere around 75-100 units of various sizes in the freezer.
Perhaps if my socialization efforts work and the new ones don't bite, I may change my mind, though I doubt it. I've heard too many comments from other breeders about them biting to expect it to be eliminated that easily.