Pros
I have done 2 contracts with UDig (one in 2007 and 2013) and both were great experiences. On my last assignment I worked with Jeff Bonniwell who placed me in a contract that I was able to turn it into a full time position. He was very informative and made sure to keep me updated with the highering process and once I was placed he made sure to keep in touch throughout the time I was with UDig. They have quality positions and if you have an opportunity to work for UDig you will not regret it. They keep in constant contact with you while you are on assignment making sure that things are going well. All of the staff work hard to make sure your needs are being met and you are happy in your position. They work with some of the best companies and offer very competitive salaries. I have worked with several contracting companies and my best experience has been with UDig. I know I can count on them.
Cons
Even though my one contract was short and the other I was able to turn into a full time position I think they could offer vacation time and personal days. More and more companies are going with contractors so vacation would be a plus.