Intensive Attachment Therapy Clinic

I am new to this forum and am looking for anyone who has had experience with an Intensive Attachment Therapy Clinic. My family is comprised of adopted twins (at age 5), who are now 13. They have never really bonded with either myself or my wife. Our children have been diagnosed with Reactive Attachment Disorder (RAD) and our psychologist suggests that we look into attending an intensive two week attachment therapy clinics. We are looking for anyone who has attended one of these programs and can share their expeiences (either good or bad). We have not made a decision about attending the program or not. We are still looking for more information. I hope you can help us out.