Vantaggi
You'll meet some crazy talented coworkers, most of the people there (at least in tech) were pretty great. Decent salary. Decent benefits. You do get rewarded more time off the longer you're there, and there are summer fridays so it adds up okay.
Svantaggi
Work/life balance is dismal Did I mention you'll work a lot? Because you will. You'll work on holidays. Weekends. Late at night. Zero job security. I survived three different rounds of layoffs before I was finally gutted. Pretty certain my entire former department is now being run out of the much cheaper office in Argentina. To be quite honest, it's a great way to put your work force off shore to save a chunk of change but not look like you're doing so, because it's technically an R/GA office. You'll get a week of severance for every year you've worked there, that's it. Doesn't matter if you've worked every Thanksgiving because of black Friday sales or whatever. DO NOT EXPECT JOB SECURITY. DO NOT EXPECT JOB SECURITY. The company does not care about you. Never think that they do. Never expect to work there for long, pretty certain my seven years was some sort of anomaly. You'll learn a lot here, so if you're offered a job, go for it. Learn, make connections with other coworkers (the coworkers are a tight knit group, I'm still friends with many people two years after being laid off). You'll have fun at R/GA happy hours and work parties, the company does throw down for good parties. Just don't expect it to last. Force a work/life balance. Don't let them work you to the bone, inasmuch as you can. Take a day off now and then to just sleep in, and not run yourself down too far. Use that place for everything you can, because trust and believe they'll use you back and then toss you out with the garbage.