I could b wrong but the t28 is a t25 with slightly larger housing and 16g compressor wheel… Externally, the only way youd b able to tell the difference is the compressor arm being slightly longer on the t28.
16g setup will yeild alil more highend, where the t28 will blow it away with spoolup time.
Recently, the price of a fpbigt28 has gone down from $750 to $599 with a t25 core.
If i cant find a big or Evo 16g ill get in touch with yah about the t28.