Diamond Eye is fairly new to the DPF Race kit scene and they did have some issues with a few of their first kits. We were hesitant to recommend them at first due to this issue, but they have now got the issue fixed and they have been doing great. Also, the Diamond Eye kits are all straight piped right now so if you want a kit with a muffler, Flo-Pro, AFE, or MBRP are the way to go. MBRP is also new to the Race exhaust market and we have done a few of their kits with good results. We have held off recommending them to people until we get more out in the filed to make sure they are fitting all trucks. The market is continually changing, what was the best yesterday, isnt necessarily the best today.