Pros
Able to focus on advisory engagements and pursue consulting opportunities/outcomes without so many external audit derived limitations compared to Big 4. Talented people with many individuals having backgrounds in Big 4 as well as industry.
Cons
Given size and breadth of possible work, not suitable for someone who doesn't know what they want to learn (Consultant-Senior Consultant), or who hasn't got solid credentials/expertise to bring to the table (Managers and above). Does not yet have a strong company culture, lots of "Individual" in the three "i"s where people work for themselves under the brand Protiviti rather than an affinity for Protiviti. New company competing with old names in the market, experienced growing pains and continues on the path finding itself (while needing to make money for RHI, etc).