What we normally do is create a manual installation task and assign the task to a collection of systems. The initial collection is normally our test users. This allows us to stage the installation and we are able to test it's replication, availability and installation prior to User Acceptance Testing (UAT).
When initial testing is complete, change the collection on this task to be the pilot, phase I, II, III, etc. collections for the production rollout. This will allow for UAT to be done, again, manually.
Once UAT is complete, we copy the task and assign it a schedule. Because the package was downloaded for the manual task, it will not require another download.
HTH