I recently started testing kubernetes using kops and was pleasantly surprised how explicit it was about exactly what changes it would make in AWS. If you get past the testing phase and want to use it conjunction with your existing production infrastructure, I found AWS's VPC peering to be a handy way to let your k8s cluster talk with existing services while keeping the kops-created VPC separately managed.
the dedicated VPC approach definitely works. But, in case you weren't aware, kops can launch a cluster in an existing vpc pretty trivially.
1. create your cluster specifying the existing VPC id and CIDR. do not use the --yes flag (I'm not sure the VPC cidr is really even used with this approach)
2. edit the cluster definition (kops edit cluster xxxxxxxxx) and just change the subnet CIDRs to whatever nonexistant ones you would like for kops to create and use.
