What are the pros and cons of whether or not to default all Packages to Units in Rhapsody Model Manager?

What are the pros and cons of whether or not to default all Packages to Units in Rhapsody Model Manager?  I have a team of a few dozen modelers working on a complex system model. We are currently configuration controlling our model in SVN, so we have turned off the setting to make every package a unit (in order to reduce the amount of CM operations we have to do in SVN). But we are going to be moving to Rhapsody Model Manager in a few weeks. And I am wondering if I should manually go into the model and make every package a unit after we convert to RMM, and change the project property to make every package a unit going forward.