Vantaggi
You access for free lots of tools that others only dream of. Because most probably you're developing one of them and use others on daily basis. You're on the bleeding edge of innovation and technological progress. Teams spread all over the world. Many opportunities to communicate with engineers from different areas: both in terms of location and in terms of technology. You may directly apply your talent and vision to your area of responsibility and this way create products that industry leaders will use.
Svantaggi
Big company is keen on protocol - please use a years proven workflow, super-stable (read matured for at least 5-10 years) tools. Those things were outdated in last century. Big company means if you're not a VP of anything you have a very long food chain above you. With this long chain it's so hard to make decisions (needs too many approvals and handshaking).