If you would like a Hatori pipe give these guys a shout:
http://www.hatoriusa.com/

I prefer Hatori pipes and it's totally a personal preference kinda thing...Are they any better than Mac's pipes?? Not sure I can say they are...

I think Hatori pipes look kewler... [8D]

I do think there is a quality difference between the Hatori and Mac's headers though...I've had three or four Macs headers crack but no problems with Hatori...Two of the Mac's headers were brand spanking new...One cracked on the first run...Someone suggested I contact "Mr Mac" (or whoever) and that their customer support is really good...I didn't sent them back because I pitched them in the garbage as quick as they broke...Oh Well...Maybe they would have stood behind them...

That YS 45 is an Awesome engine!!

Chuck