If you're using PAM on more than one machine, it's best not to edit the same items at the same time. PAM will detect if you have conflicting changes when you attempt to use Commit Changes on work-in-progress. However, you are likely to lose your changes in that case because PAM cannot guarantee the integrity of the data being edited in two places.
Ultimately, it stores the data in your MS SQL database, in the same way as a RMS. You would run into similar problems with RMS if you try to edit the same item simultaneously on multiple machines.
The best advice we can offer is to filter the items you're working on by machine, so you are working on different sets of items simultaneously. As soon as there are two instances of PAM editing the same set of items, only one instance can "win" and commit its changes.
The filters in PAM are very granular -- for example, you could apply a filter to edit items only in one brand, one department, one category, and one subcategory at a time. In general, if you are editing on multiple machines, it's best to stick to editing smaller subsets at a time and to coordinate even a little with other staff members to ensure you're not duplicating or overwriting others' work.
Finally, if you do find yourself in conflict, resetting your filters, or closing and reopening PAM will reset the data to the freshest available from SQL Server.
Hope this helps!