I have the full system. If I could do over I'd the 1/2. Only serious gains are up at the very very top where you hardly spend any time. I've seen reports where the half systems to much better down low and mid range. I don't think I really lost anything down low from the full, but I didn't gain alot neither. Plus, I have heard the half system is a little louder due to more back pressure. Either way, it really wakes this motor up. Spins up so freely and fast. Overall, I'm still happy. Don't know if you guys have seen the Zard system but it's becoming pretty popular and word is performance is great. Like the half system, definately cheaper than the full.
http://www.section8superbike.com/04-06-749s.php
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