I'm guessing iPhone 6 is out of stock because it is such a popular phone. My daughter has the 6 and I have the 6 plus, they are amazing devices.
In my opinion Apple finally got it right. I didn't like the fact that they refused to make bigger phones and also limit third party involvement. Now that they have made the bigger phone an option (I totally feel that the 6 plus is too big for many people but personally it's perfect for me), it ticks all the boxes.
Also, I can finally have Swype and other apps which made me go running back to Android in the past. I am not saying there is anything wrong with Android at all, I'm a huge fan, but for right now I am loving my iPhone 6 plus.
The thing that excites me more than anything is the Apple watch, I can't wait to see exactly what that will do, although it took me a while to realise that I won't be able to afford the gold version!
I know it's hard to wait when you want something, but I honestly believe that the iPhone 6 will prove to be worthwhile for you too - so keep checking and hoping, it won't be long until it is back in stock.