I was told about AGR by a very good consultant who worked through them and was impressed from the start with their rigorous process of checking references before taking on a new consultant.
Since becoming a consultant in 2005 through an AGR placement, they have been totally professional and have kept regular contact without being overpowering. The placements I have had through AGR have been well suited to me and I get the impression that they take the time to make sure they match the right consultants to each placement. When I wanted to move placement, AGR were able to offer me a choice of alternatives and were able to arrange an interview and secure a new placement within 3 days. While I'm sure that this is not always possible, I feel that the AGR team work very hard to get consultants placed as soon as possible.
Additionally, the consultants that I have met over the years working through AGR tend to be very good and well respected in their areas, and this must reflect well on AGR also.