Huh, guess I was wrong but they sure did look like titanium, I saw it at the Honda booth that sucker was bone stock, I'm prolly wrong tho since titanium obviously doesn't have a magnetic property. Still I wouldn't see like yoshi making a inferior product to the stock system
they are still stainless.. so when they're new, once they've been heated on a motor, they turn a nice golden color... most stainless headers do this.
Header design involves tradeoffs... you can easily make more PEAK power, if you are willing to do a design that is less efficent elsewhere..
the Yoshi system (and all good aftermarket headers) are tuned so they do create more peak power... however you have to understand they will lose power elsewhere to do so.
the OEM header makes a large amount of power everywhere.. it doesnt choke the motor... but going to a shorter or larger header design, will increase peak numbers... and thats how they sell aftermarket headers... but in real street riding... it actually sucks worse then the stock header.
as far as the racetrack goes.. unless you're in the A group runnin ohlins, slicks, etc.... its just a waste of money.
if you're drag racing only... sure. go for it... but you probably want to find a different bike to drag race anyway... drag racing the new CBR is like autocrossing a pickup. you can do it. its fun. but there are better vehicles out there to start from, that you wont even touch because you're starting from so far behind the curve.