I currently use a HANS device and have been using on for the past 6 years. I started using the HANS when driving my SC Dragster because I had two spinal fusions i my neck and the Ortho Surgeon said he would only let me drive if I used the HANS. The wife agreed. I never had any problems associated with using the HANS, it just take a little bit of getting use to. I found that with the FED, it is better to put the HANS and helmet on before I get into the car and then my pit guy helps me finish the belts over the shoulder. I have been usin the HANS in my FED since 2010 with no problem. I also have the NHRA mandated - Good-Guys rules ISP Helmet pads on the sides of the roll cage.