Pros
People at R/GA are generally nice and invested in their work. While there are some exceptions, it seems like most people there have a pretty good work/life balance, and don't pull crazy hours to meet deadlines. I really liked my tech directors while working there; they were always supportive and willing to listen when I had issues or questions. As far as I can tell, each of the offices that R/GA has are all very well-equipped. The IT department was also pretty good about getting software and tools for devs. I never felt like I was under-equipped to take on whatever projects they gave me. The NYC office has a few perks that were pretty nice. In particular, there is a coffee bar there that is very reasonably priced ($2 for any espresso drink), and pretty affordable catering around lunch time.
Cons
Your work/life balance at R/GA is pretty dependent on who your team leader/producer is. While most of my projects here have been calm enough that I've been able to pull a normal 9-5 schedule, there have been exceptions where I have had to come in at a regular time, but stay late into the night, sometimes leaving as late as 2am. I was told by others who had been at the company for longer that this was unheard before, but it still stands that this was my experience for roughly 2-3 months as we neared launch. The review/promotion process at R/GA is also pretty frustrating and slow. The company is locked in to an annual schedule for performance review and promotions/raises, which means that you have to wait for quite a while for your good work to be recognized. If you're a skilled dev who's looking to move up quickly at your next gig, maybe this isn't the place for you. Finally, projects at R/GA are dependent on client contracts. If there's an unexpected change in a client's business plan, or if there just isn't enough work coming in for your particular specialization, you might find yourself on the way out.