First question: "When can I buy an iPhone 6"
Second question: "Take me to the iPhone 6"
Siri is a bit lazy nowadays. The first question Siri should have just loaded the page for me in Safari. The 2nd question Siri opened the Maps app and gave me directions so that was pretty good.
I asked the same questions of Google Now:
"When can I buy an iPhone 6":
"Take me to iPhone 6":
I think Google Now answered the first question pretty well, but the 2nd question I felt Siri's answer was better because it actually showed me where and gave me directions. So Apple 1 and Google Now 1. However, I don't think Siri knows what an iPhone 6 is yet, and just keyed off the word "iPhone" with no distinction for 6. Google Now recognized 6 and took me to results specifically for the iPhone 6.