Best HFC's For my Setup
 

Breathing mod's: Mrev2, 5/16 spacer, nismo headers, hr y-pipe, amuse intake pipe and nismo drop in filter.

Looking for Durability, fit and finish, and cleaness of sound/flow.

Doubt you'll see a difference between both.

Go with FI 300 cell; only reason you see it losing in the polls is because it isnt as popular as crawford, since FI is somewhat new.

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Bump for FI. I wouldnt go any other route besides FastIntentions. Great products, great quality, incredible gains and sounds, and the best customer service to back it all up!

you can't go wrong with either. crawfordz recently upgraded the bracing on their cats, so they shouldn't have any cracking issues anymore. i have the FI metallic cats and couldn't be happier.

https://g35driver.com/forums/intake-exhaust/122425-fast-intentions-300-cell-metallic-high-flow-cats-pictures.html

i've also heard good things about the random technology HFCs. you may want to look into those as well.

i dont know anyone that has them, but the altered atmosphere HFCs look really nice as well.

What's the life expectancy for HFC's? I've heard they go bad after 35k miles or so and sound like a bunch of marbles or beans rattling around....

what?

I have sedan - on my car the Crawford’s didn’t really change the sound of my exhaust much... which for some that might be good, others that might be bad. I have gen 1 Stillen which is a little loud to begin with - I was hoping the HFC would make it a little throatier/deeper (it did a little, but not much)... I have heard others say they aren’t as loud too... so if that's an issue you might want to choose Crawford.

I've heard good things about FI, I just don’t like how the sedan exhaust issue has gone - I have Stillen so I don’t care about their exhaust I just think it's a little goofy what’s going on there.

I absolutely felt good gains with Crawford HFC - without a doubt there is noticeable trq!

I bought some of the original Crawford's for my early, bought in July 02, 03 sedan. I put 22K miles on that car. When I returned my sedan off lease for my new 05 coupe, I just had them swap the Crawfords to my coupe. 13K miles and still going strong. I had these hooked up to DC headers and Borla exhaust on my sedan and now have them hooked to the same DC headers and JIC Y-pipe w/Fuji exhaust. No issues. Sound and perform great so far.
I have Crawford Plenum as well. I would have gotten the headers if they had come out to market before I bought the DC's. I think they have excellent products and service. Can't go wrong with Crawford IMO.