You're right, the X-crossover isn't the full width of the pipes, that was poor wording while typing fast on my part. It flows a hell of a lot more effectively than that little H-pipe does though.
If you swap in the HKS for the FI and see gains in a fair before/after dyno, I'd be insanely surprised. I'd bet anyone that wants to try that experiment $100 you'd lose power actually. That just based on intuition and staring at pictures of the two
If they were priced similarly I'd say who cares, but given the insane markup on the HKS unit, I just can't see any reason why it would be sane for anyone to buy it
