Pros
Big organisation with big budgets, can sponsor whatever makes employees "happy" such as fancy events, kitchen equipment, games, teambuildings. As a designer, you have plenty of space to experiment. The UIs are really bad, it is easy to make them better. Good for juniours who need to screw up few things first. You will get a top end equipment such as latest model of macbook, all perriferies you need.
Cons
Culture is terrible. Typical corporate culture even though they try to look like cool team. It is not truth. Problems are fixed with free lunch and then the leaders brag about it for weeks. There is not enough designers, expect overload of work. More then designing you will be business modeling. Designers are generally not considered on the same level as PMs or DEVs. You will need to build your own position. Not easy for juniors. There is a lot of pushbacks. Research is not the standard. If you want it, you do it. Do not expect PMs to base their decisions on research. They use gut feeling or middle management advice they do not completely understand. Middle management is not helpful, they ale a blocker from being fast and agile team. They block things from release because they want things to be 100% ready. They do not like to risk anything.