Using Membership & User Sync

We would like to use Membership to give our live paid members access to our beta development site.

Is it possible to use User Sync with two sites running Membership?

I have a live site with Membership (v1) and a development site running Membership (v2). I've installed User Sync on both sites, made the live site the master and the development site the subsite.

On both the live and the subsite I have a subscription labeled "Subscriber".

After syncing users, none of the users show up in the development sites "Subscriber" list of subscribing members.