Pros
The management philosophy is unique. It attempts to take those things that work well in the free market and apply them inside the firm. Things like property rights (decision rights), incentives (pay for performance), and encouraging employees to act like owners and start and grow the business as an entreprepreneur would. Being privately held is a huge competitive advantage because the company does not have to behave as those who fear wall street punishing their stock price if the last 3 mos do not meet financial expectations. This allows the company to look at things over a long term - which is what all boards should be doing but do not.
Cons
It is a very 'bottom line' company, not that that's a bad thing, but the bar is constantly being raised and this can lead to burn-out. The upside is that if you perform, you really have the opportunity to earn beyond your peers at other companies.