HKS for sure. The tone before VTEC is mellow, but after VTEC it is like all hell broke loose. I have it and highly recommend it.

 

there's some ups and downs for both exhausts. i ended up getting the invidia. invidia looks better than hks, but hks has better sound. invidia is inexpensive compared to hks by a lil. hp gain dependent on other things, if you gain any its 3/4 hp at most.

invidia is loud but controllable with the throttle.

 

Invidia all the way.

The HKS does sound nice, but IMHO it just does not sound as good as the Invidia. There is that drone with the Invidia....but its controllable with the gas pedal, and if you get a test pipe it almost completely disappears.

I guess if you have it narrowed to those two exhausts, you have to decide if you are hardcore or not. The Invidia is definitely extreme, and sounds like a pissed off cat on steriods at wide open throttle. I have had mine for a month, I drive the car every day and have not regretted the purchase once.

 

I also have the ividia and its only slightly annoying if you're just kind of coasting somewhere. As long as you keep on the gas its sounds almost like a normal S. Now when you're not yea its loud and there is definately a drone. I don't care though. At WOT(wide open throttle) it sounds like sex with jenna

 

V3 Invidia + TP... Do it!

 

If you actually want some gains, get Invidia... if you want a good sound and probably not realistic gains, get HKS. If you want both and do not mind the loudness of the exhaust, get the Invidia.

 

I have Skunk II(which is pretty much Invidia) and I love it. The exhaust has a nice deep tone and sounds great in Vtec range. Alittle loud sometimes when your trying to talk to someone on the freeway but it is well worth it.

 

I have an HKS exhaust on my S2000. It has a very nice tone. I think it's the best sounding exhaust for the S2000, just like how Taitec exhausts sound the best on NSXs

 

HKS with a test pipe sounds awesome.

 

Invidia's sound at vtec and up can't be beat and it's also a dual that has been said to gain the most HP. But just like a couple of peeps already stated, it isn't for you if you're not extreme.