Pros
Company management leaves you alone as you provide staff augmentation to a client. Much work is done as a subcontractor to a Prime. The back office (HR & Finance) is friendly enough and seems to be trying to help if you have questions.
Cons
One is more of a pass-through than part of the company, as little information is shared. There is minimal communication unless a recruiter asks how you are doing (but they can't fix anything anyway - and get paid to keep your billing or the account manager is trying to get more people staffed on your project). Benefits aren't the greatest and seem to change each season; you may or may not get your bonus depending on the mood of the CEO. The leadership team (CEO, COO, CDO) grew up together and are prone to "Group Thinking." Most of the positions are contract-based, meaning that once the contract ends, you likely will be out of a job. Sometimes Clarus may find you another, but don't count on it. Limited training, continued learning, or mentorship, as you are likely on your own with the Prime and the client- is not necessarily inadequate if one has the skills & experience. With the work being under a Prime, you might expect your pay to be lower than actually working for the Prime (that is expected). Also, if you are salaried, I recommend you take your earned PTO as you may not get it paid out (depending on the State)