Testingour first targeted multicast deployment

I have my Multicast Domain Reps all set up.  They are machines across the domain.

We want to stage the files on all MDRs first and then deploy later using caching. But I want to see things working on a much smaller group first.

So I am targeting the package to just several machines on two different subnets. Is  Targeted Multicasting smart enough to know only deploy the package to the MDRs that are on the same subnets as my client machines I have specified . . . . .or will it distribute to ALL MDRS??

Thanks!