Pros
Some really interesting people work at Gartner, and you can generally engage with them quite easily. Clients are really open with you about their business and even personal objectives.
Cons
It's really pretty shocking how sexist and racist Gartner really is, people openly make jokes about how women look, and there are almost NO people of colour working in Gartner, and none at the leadership level. The only senior woman, is, you guessed it, HR. They don't even try and camouflage it like most dinosaur companies do, they just don't care at all. It's like they have some secret pass or something. Customers are just an annoyance, there is absolutely no understanding or appreciation of Customer Experience at all, at any level. Mid level leadership is immature, petulant, and frequently quite abusive.