Pros
Great people - I was very impressed by other colleagues, particularly in Houston HQ - both with their technical and process knowledge and their willingness to help when our new team abroad needed assistance. Good work-life balance - the company in general and the direct manager were quite helpful whenever employees needed to adjust work schedule to family duties which is very much appreciated when having children. Many opportunities to learn, in any IT domain you wish - great for people starting their careers.
Cons
The famous founding culture as described in HP Way book is long dead. Nowadays, the company suffers from all the bad traits of large corporations. Lay-offs repeat every year, no one knows whether a colleague sitting next to him will be made gone next quarter. A lot politicking. It matters more how things appear rather than what they are. Fear of boss disapproval is omnipresent. When you disagree with your boss, you are fired.