There are some people who don't necessarily want maximum HP. Some also enjoy doing their own work and modifications instead of just writing a check.
There is little doubt that Carpenters exhaust is likely best for higher engine speeds. However not everyone wants that. I for one. That's why I chose TTS. I enjoy working on my own bike and my next step will be a Carpenter Brute, my TOR's no longer breath well enough. That's why I really need a local tuner.
Had I wanted the fasted quarter mile bike I'd have went with Carpenter. Day in and day out with the type of riding I do I seriously doubt I would be more pleased with anything other than what I have. Also it's a work in progress.