Pros
I’ve been a part of the IGT team since the beginning and was part of TRUE Communications, a PR agency that was absorbed into IGT. No question that IGT is a high performance organization that is focused on delivering amazing work for clients and that takes a lot of effort. IGT is not quite two years old as of this writing and has grown rapidly by developing relationships with top tier clients. There's no question in my mind that this consultancy is going to continue to scale and will deliver truly creative work (vs. work that just wins awards.) IGT has grown quickly during the past two years and has taken growing a culture seriously. The management team her is focused on supporting team members and have backed that up with great benefits, bonus comp and increases in salary.
Cons
This is not limited to IGT, but to any type of consultancy or agency: Working at a consultancy is demanding and dynamic and is not for everyone. If you've tried agency work in the past and found that being deadline driven and accountable is not for you, then you should definitely skip IGT or an agency of any type.