As described in the Sandbox Types documentation:
Different sandbox types support different activities.
A Developer Sandbox environment isolates changes under active
development until they’re ready to be shared. A Developer Sandbox is
designed for a single developer, although more than one person can log
in to the sandbox at a time.
Developer Pro Sandbox
A Developer Pro Sandbox environment provides the same functionality as
Developer Sandboxes, but offer increased file and data storage. A
Developer Pro Sandbox can host larger data sets than a Developer
Sandbox. Use a Developer Pro Sandbox for tasks such as data loading
and integration testing, user training, and the development tasks you
do in a Developer Sandbox.
Partial Copy Sandbox
Partial Copy Sandbox environments include all your org’s metadata, as
well as a sample of your production org’s data that you define by
using a sandbox template. To create a Partial Copy Sandbox, apply a
sandbox template at creation time. Use Partial Copy Sandboxes for
virtually any development, testing, or training purpose. The only
tasks for which they aren’t well-suited are full performance and load
A Full Sandbox is an environment with a replica of your entire
production org and all its data. Use Full Sandboxes for any
development, testing, or training purpose, including full performance
and load testing. Apply a sandbox template so that your sandbox
contains only the records that you need for testing or other tasks.
To sum it up, the major difference between each sandbox is the refresh interval, the available resources and the type of data that is being copied.
If you are willing to provide training to your employees or perform more specific tests such as integration testing then having real data could be very beneficial for your business cases. So depending on your company size and the use cases you'd want to perform each Sandbox has it's own advantages.