I got the M4s. Just happened to be on line when chris re-offered them. I'm combining them with an 06 headder which I had ceramic coated (black.) I'll also be adding a PCIII so there's a few things going to change all at once. I'm looking for performance and sound aesthetics but I'm also hoping to eliminate an overheating problem I have when I'm pushing it hard on twisty backroads. I've gotten leg burns just above my boots right through my pants. I'm keeping my stock system in reserve in case I get cited by the Highway Patrol. It doesn't happen often but you can get cited for removing cats in California. It's has happened to me before. You know how it is...some cops like bikes and some don't.
Unfortunately I have to go into the hospital for a "proceedure" this week. I'm not sure how long I'll be recuping but I hope to get the system mounted in a couple of weeks. I will post the results of the modification. It's always interesting to share and compare.
Ride safe y'all. 
008 ZX14R Ninja ... Midnight saphire blue with custom lightning bolt paint job, Kenny Rodgers KRTuned mufflers, Corbin custom seat, Marchesini wheels, Dunlop Qualifiers, Dyno Jet PCIII, custom FAICS map, Dyno Jet Ignition Module, K&N Air Filter, Supersprox 44 tooth sprocket, Zephyr 16 front sprocket, EK chain, TRE008, MRA windscreen, Race Railz frame sliders, Sato Racing axle sliders, ST Machine brake & clutch levers, Engine Ice coolant, Muzzy aluminum fan, ceramic coated headers and midpipes (cat removed), Vortex Rear Sets , Pro Comp Stearing Damper, Pro Grip Gel handgrips, Gen Mar clip on risers, Dowco tank bag, and a Rumble fender eliminator.
Removed GPS.
2005 Harley Davidson Dyna Low Rider, 1442 CI fuel injected, 65 HP, lots of chrome with 24K gold overlay detailing. Sure is pretty!
Will I be allowed to publish a picture of my new upgraded one here??