Welcome back to the Wefugees Community and thank you for your question.
One advantage of the residence permit according to section 28 (there is no 28b) is, that you can apply for a permanent residence permit (Niederlassungserlaubnis) already after three years of holding a temporary residence permit. For more information and a full list of the requirements see, for instance, this website (exemplary for Berlin residents).
If you are holding a residence permit according to section 25b, you can apply for the permanent settlement after holding the temporary residence permit since minimum 5 years.
I hope this helpful and please don't hesitate to get back to us with any further questions.
All the best,