i'm in the army, i'm a welder. i purchased a muffler off of ebay for 8 bucks. cheap ya does it work hell ya. i took out the third cat and silencer. 36lbs in weight. i replaced them with straight pipe. the total pipe including muffler weighs 20lbs. welk i'm i tell you it the best sound i've heard. i also have and intake on this. all together 43hps gained dyno tested. the tech stated the balance is perfect. and you can feel it. give you good take off. i also had it smogged which it passed, and emmissioned,passed. you still have two cat. near the engine. remember lexus is a low emission vehicle a lot of restriction on it. takt the restrictions away. pure jap horses .