When it comes to naming conventions, I don't think there is any best practice
here.

Yes, you can name your virtual server and your instance name identically.
They are in different name spaces, and so there won't be any conflict. For
instance, if your virtual server name is NYCSQLABC02, you can name the
instance on that virtual server as NYCSQLABC02, and you access that instance
as NYCSQLABC02\NYCSQLABC02. The advantage is that you don't have to remember
which instance goes with which virtual server. The downside is that the
virtual name \ instance name combo can get rather lengthy. We used this
naming convention for a while until we were tired of the long name, and opted
to just use SQL1, SQL2, and so on for the instance name.

Linchi