Hello,
You can defiantly replace this screen yourself on the iPhone 6. I will be adding a guide to iFixIt for it, it is much easer the the 5s.
However if you do have Apple Care or Insurance you are most likely look at a much cheaper fix, since the phone is still so new. I say this because part cost for the Front Assembly of an iPhone6 4.7 still ranges between $130-$200 just for the part alone.
Most Cell Phone Repair shops are charging between $199-$299 for this repair and if you have Apple Care your looking to spend $109 for it which is a great price considering you have already paid into Apple Care. So...at this time i would let a pro handle it.
Hope this helps, if it does please mark it up!