Pros
Excellence in technology and ability to push the envelope in its key, moneymaking markets. If you work in the semiconductor or display areas, in certain product groups, life is relatively easy and you are personally rewarded for the group's success. Some people reading this may ask: easy? Yes, if you have worked in both sides of that coin, you would know what I'm talking about. Is a high technology engineering job that rewards in ways few engineering jobs can.
Cons
Conversely if you are in semi or display in an area that the company is struggling in, life is hell. You might do a spectacular job, and never be recognized for it. This is why people flow out of areas like etch or wet chemical products and try to get into the moneymaker groups. Your management or your group will be blamed for failures that could be cycle-related or due to the customer's desire to play AMAT against another supplier. You want the reverse to happen - you WANT the great star performers to take up the challenge of the struggling businesses. But after a short time at this company, it will be visibly and abundantly clear why people do not do this. Company is so dominant that oftentimes, your main competition/nemesis in the marketplace is another group in AMAT.