Pros
Jacobs is a large well known company with a good reputation. They have a fairly good management style and a diversified domestic and international business base that covers most of the engineering fields and seem to support lateral movement into other positions and business units. Employee retention is good as the have an ability to place good employees in other positions if one is lost (may requrie a willingness to relocate). Benefits are on par with the other major engineering firms.
Kontras
Large company that does not always focus well on business untis that are outside its main portifolio of systems and industrial engineering groups. For example, I worked under a contract to support DoD research and development, and Jacobs didn't seem to quite know what to do with us at times which caused some confusion in goals, etc. Also structure for this particular contract was very flat offering less than ususal upward mobility (though this is typical for many DoD contracts). Pay scale and benefits including medical and 401K kept consistent (read as lower than average commercial rates for equivalent positions) with the civilian service contingent that also supported the DoD there, but leave was not. Profit sharing was almost non existant. Again, this is par for many DoD contracts, especially in the world of lowest cost technically acceptable contracts, which seems to be the way DoD is moving.