Its a matter of individual choice, BBE. The hospital wont tell you that if you delay clamping you don't need the vit K injection, because it is their policy to give it regardless. As far as I'm aware, delaying the clamping won't increase baby's level of vit K, but I'm no expert.
There are articles on vit K and delayed cord clamping on here I'm pretty sure. It is up to you as to what you choose for your children.