Pros
I worked for three staffing firms and had inside views of dozens more. Kforce as a whole is one of the better ones. Pay, management, and opportunity are generally as explained. While one office may be better or worse than another, the opportunity to succeed and make a six figure income in the second year is substantially higher at a Kforce branch than most firms. It was an excellent mid-career company. It would not have been a good entry level position, though those who were at the headquarters at Tampa might have felt differently.
Cons
Kforce pitches a great culture, but they are in essence a high quality call center. They fill an important niche for other public companies, but to be successful, you need to be a smile and dial recruiter focused on profit, not on placement. Nothing wrong with that, but numbers are more important than the "right" thing. I remember one time being chewed out for a placement that brought in $40,000 in gross margin because it didn't match the regional manager's need for a higher margin percentage. I made $8,000 on that contractor, who wouldn't have taken the job for less. It was right for me, right for the contractor, but bad for the manager, who got their bonus on percentage. It was the only low margin contractor I had at the time.