I know this post will be self-serving, so I'll get that out of the way right now. However, I usually try to guide Travelers to the smaller companies. The wages are 10-15% higher, the housing is usually better, and the people you deal with are typically happy to talk to you and much more informative and honest with you. Living in Omaha (Hub of the Travel nurse companies...3 of the top 4 largest are based here), and working for both kinds (HUGE and Start-up), the smaller companies typically have more flexibility with you, and will work harder to get you where you want to go, even if you don't meet 100% of the requirements. And if you are a new nurse, or a nurse with a gap in employment history, you can forget about the Big guys. They won't even give you the time of day. I won't use this as a recruiting tool, I won't post my email, phone number, or website, or spam you guys, but the company I work for was started by a childhood friend of mine who was sick and tired of how the larger Nurse Staffing companies do business. He not only found enough investors to start a sucessful business, he was just named "entrepreneur of the year" in the Omaha-metro area, which is no small feat! Its because he keeps his word, does right by his RNs, CNAs, CSTs, and understands that sometimes you have to deal with more than one staffing company when you have a very specific need. We not only will help you find the job you want, we'll recommend other agencies to our clients if we cannot find a job that they might have.
So you can join in with the Big Guys, get paid less, and get treated like a number...OR...you can join up with a smaller company, get paid more, and be treated like a friend.
There is my completely biased, but honest opinion!