If you have a desire to purchase (which is what I would do) go for the Adobe CS6. As mentioned, you can connect to the cloud and use a new version, but it has a monthly fee.
How does that feature work when saving the Photoshop file? Can it be saved with the linked file not included? How does that "missing" link then affect output from the layout application into which the Photoshop file is placed?
Adobe Master Collection CS6 is correct, however, depending on what your looking for, you may just want Photoshop itself as the entire collection is very pricey.