Pros
The people can be friendly depending on your race, nationality, and country of origin. They often prefer people of Indian-decent or of H1-B status. I suppose if you are Indian, that's a definite plus as you'll have a nice and long career here. The pay is pretty good. They've been tightening their belts lately and cannot offer the pay rates they previously did but it's still a decent salary although a lower bonus percentage.
Cons
If you are in I.T. expect to be working with offshore employees who focus on one thing and do it averagely. Mphasis doesn't like outliers or over-preformers, they try to work them out of the system as quickly as possible. This is because from an operations perspective - they can accurately predict and measure average performance whereas over or under achievers can throw off estimates and expectations. This is much different than working for a usual US-based company. The other con is the "bait and switch" tactic that the company uses to attract talent. Their advertised jobs for software engineers will list popular stacks and technologies but upon joining the company those engineers will be handed a product called "Mendix" to use. Roughly 80% of their time will be spent in this BPM tool and the rest either in meetings or actually working with the advertised technology. There isn't any path to communicate the needs and complaints of the employee. The material and hiring process will explain that you need to go through HR etc. and that there is an open-door atmosphere... That's all well and good, expect when you are sitting across the table from a CTO who sees you more as a line item on a budget and less of a person or individual. There are a considerable amount of layoffs and hiring US resources is tough or even frowned upon.