Good ExperienceThe good thingsLearn good industry best practices, technical knowledge
Salary is pretty competitive with the market, but also depends on the seniority level and the project industry.
You can also get a pretty good amount of business knowledge of the various industries.
The challengesThe exposure to various new and latest technologies are pretty limited, especially if the project you're working on in something which is on-going, and chances of jumping to a different project with a different exposure are very very limited, unless the project you're working on has reached end of life.