I installed a pair of off-road JBA mid-pipes on my Charger and was not very happy afterwards. The stench from the exhaust was so overwhelming that I would often get headaches sitting in traffic. I started shopping around for some catalytic converters that I could have welded in. Originally I had my mind set on Magnaflow as I've used them in the past and their cats worked great. I needed a spun cat due to tight clearance between the frame rails and the exhaust, and the cats needed to have the rear oxygen sensor bung built into them. Magnaflow did not offer such a combination. I came across the Thunderbolt converters on eBay and they met my requirements. Spun converter with the bung built in, and they were only $55 each! I looked around online to get some reviews and only found a few reviews about them, and all were positive so I pulled the trigger. Cats arrived 2 days after ordering them, and while I will admit I was a bit skeptical of the quality when I opened up the box and looked at them, they were exactly what they were advertised as. Had them welded in a few days later and bam! Immediately took away about 90% of the exhaust smell and really didn't quiet my exhaust down all that much. I did keep my O2 spacers in place just because I do not want any CELs, but I'm pretty sure it's not necessary. These cheapo converters were worth every penny and I wouldn't hesitate to buy another pair... If anyone is looking for replacement converters for cheap, I definitely recommend these.