Vantaggi
Cool technology. You work with some really nice people. Nuance has good brand recognition, so it helps when looking for your next job. They tend to pay well, knowing that the hours expected and the level of frustration are high. If you are a individual contributor or low-level manager, you can hide, do you job well, and survive - as long as you don't get impacted by a layoff.
Svantaggi
Most people only last 6-12 months. HR knows this, and bases their HR strategy around it. Nuance does lots of M&A, which is followed by layoffs. If their numbers are low, they will also layoff people. Senior staff get paid really well, with lots of stock options. So most of them are just toughing it out until their stock vests, and trying to make themselves look good so they don't get fired.