Pros
Many nice people work there and co-workers form really strong relationships. Across the board the rank-and-file associates are some of the nicest people you'll meet. Generally not micro-managed, and employees are given a lot of flexibility to do their work.
Cons
That pay is based on performance is a farce. Pay is mediocre and there is limited upside yet substantial downside. There is no career potential at Gallup. You will hear beautiful tales, rehearsed over the years, about how you will be fulfilled both financially and emotionally by doing a job you love. If you let this siren song enchant you for too long once you realize that it is just an illusion your career will have suffered a large step backwards. Employees are required to work 2200-2300 hours per year. If you take 2 weeks of vacation that is okay, but you still need to hit that 2200-2300 and since you took two weeks off you'll have 50 weeks to hit that 2300 hours. The internal employee engagement surveys are used to ferret out employees that have complaints (no matter if those complaints are legitimate). Upper management openly and unabashedly acts in a puerile a dogmatic manner.