It's not like Bell has seized the job with remarkable performances. Dwyer has a higher per carry average (4.8 to 3.3) , a longer run (30 to 25) and more 20+ yard carries (2 to 1). Use them both and may the best man win but don't just give Bell the job until he outright takes it.
Playing Fantasy Football does not qualify you to be the in the front office or on the coaching staff of the Pittsburgh Steelers. They are professionals and you are not!
How many TDs does Dwyer have?