Pros
If you're an engineer, there are always plenty of interesting challenges and opportunities to learn new things. Xilinx is/was jam-packed with many highly-innovative and talented people. Xilinx parts are typically used in leading-edge applications so you constantly have exposure to new markets and applications. Likewise, Xilinx generally employs or pioneers leading-edge technologies. Despite its many problems, Xilinx is a leader in its market segement. It has a larger share of market than all of its competitors combined and generally receives high marks from customers for its design software and product support.
Cons
Far too much internal politics, needless layers of beauracracy, and too little employee empowerment. Many mid-level managers have little budget authority! Xilinx strives to be a $5B company but already has bloated beauracracy only enjoyed by major governments. Too much favoritism instead of meritocracy. Xilinx often hires from outside instead of developing and promoting the people that actually know how to make the place operate. Many times, this distracts the productive employees because they once again have to train another highly-paid senior manager or executive. In contrast, Xilinx is too inward-focussed when it comes to technology. Many times they re-create the wheel instead of leveraging or exploiting existing technology. Like in the Financial industry, too many executives and senior level management are too highly compensated for what they deliver to back to the company.