Pros
Great benefits, unlimited PTO, receptive to salary negotiations, there are some really great people working at IA. Firm has done well recently and gives generous bonuses/matching. Also is an ESOP. The firm has really made efforts to unify all the offices in recent years and it shows, biggest perk is having so many office locations you can transfer to or even work from temporarily. IA was always really flexible with schedules and the CEOs really care about their employees. I also found if you are interested in getting involved in the organization/learning a new role you are always invited to as long as you make it known. Great firm for young designers who want to get "thrown into the deep end" so to speak but experiences vary by office depending on regional management.
Cons
Larger organization so you have to be self-driven, the resources are there but you make your own way at a firm like IA which some might not like. Some offices are not very strong on the design side and working with a remote design team can be challenging. As a whole IA does a lot of great work but for some reason is not as recognizable or awarded as other firms in the industry. As with most large companies, there are a lot of really great people in leadership but also some terrible leaders - recommend you ask around and avoid the not so great ones.