If I recall correctly, the Top Speed exhaust is not a full cat back system, and doesn't replace the Y-Pipe. It also is not a true dual exhaust system like the FI TDX system. However, you are correct - it is much cheaper, and you won't have to wait months to get a brand new FI TDX system.
That being said, the FI TDX system is a truly top notch exhaust, made right here in the USA by Tony. It does produce more power than the TS exhaust, and personally, I think it looks better. It's really down to what you are looking for in the exhausts - they both sound different, and if power doesn't really matter to you, then the only variables are sound and price.
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2012 Pearl White 370Z GReddy Twin Turbo
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