Vantaggi
The people are great, and working on large AAA titles is very enticing and a lot of fun. You'll gain great experience here and it'll impress recruiters when seeking future employment. There's never any layoffs and the stability is nice.
Svantaggi
Ubisoft has a few consistent problems that you'll hear repeatedly when speaking with current and former employees. The company doesn't pay well, but the stability of the company is a good counter to that. However, Ubisoft isn't the greatest when it comes to promoting their employees. Talented, hard-working. people will deliver consistently great work and they still have to prove themselves to get a promotion. You'll hear reasons for being rejected for a promotion like, "You're too hard core to work on this more casual title." Seriously? Ubisoft's habit of doing this means that many employees leave for other companies to prove themselves and then return to Ubisoft; meaning that it's a great training ground but if you want to work in a position your skill set is best suited for then you'll likely have to leave to achieve it. It's a shame that they don't seem see the value in their talent, but other companies most definitely will, and they'll pay better to boot. During my personal time at Ubisoft i was rejected for a promotion more than once. I left and I'm doing the same exact job that I was turned down for at Ubisoft, and I'm willing to bet dollars to doughnuts that I make more where I am now then I would have doing the same thing at Ubisoft.