I purchased a set of linked roller lifters indirectly from Ruben Racing Cams. I had less than one thousand miles on lifters when one mechanically failed. I contacted the business that ordered the lifters for me from Ruben Racing Cams and they said that they would be contacting Ruben to try and rectify the problem. I heard back from them and they said that Ruben did not care and would not warranty the part. I was unsatisfied with the answer since the set of lifters cost $460.00. When I spoke to Ruben myself, he said that it was not his problem and he does not manufacture the lifters, however his name is stamped "RUBEN" on the link bar. He told me he would give me a deal on replacing the broken lifter. I explained to him that I was not willing to pay for a new pair since a part like this should not break like it did. He tried telling me that my Comp cam may have also caused it to break. Upon further investigation, I removed my cam and observed that the lifter removed approximately .040 of material from the cam lobe. It appeared that the roller on the lifter stopped rolling and damaged my cam. The lifter also damaged two roller rockers. Ruben was unwilling to help me and do the right thing. I will never do business with this company again. Ruben doesn't know the meaning of customer service. Buyer BEWARE.