I have used the hmf quiet core in the past with excellent results. I do not know the db level with the qk installed but it is signifacantly quieter than without it.

 

As for speedwerks dyna, holy shi*!!!! Thats twice as much as i paid for mine!

 

Our ex. is a full system too that is why our ex. is more than others. The stock systems normally come in around 85 db + but db's arn't everything the human ear is more sensative to certain sounds than the db gauge. I would wait to hear any of them before making your desicion if you are concered about noise. All of our systems come in at or under 96 db's. If you guys have trouble on our site you need to remember to click refresh everytime you go back to our site so that it updates.

 

i bought an HMF UTILITY SERIES with quiet core ............... alot louder. i'm the president of an atv club and deal with land owners alot. stalk exhaust for an ac 650 is around 74 db (so the head mechanic says at the dealership). it did give me more power and a quicker responce,but i would not recomend it to those who travel close to homes or late at night..............