With the 7000 as master in ArubaOS 8.0 (non-MM deployment):
- The master controller must be a 7030 or above
- Access points cannot terminate on the master (it takes the role of the MM, which also does not terminate access points)
- Airmatch is not supported
- Monitoring of things like UCC, Airgroup and Clients is individual to each controller (in an MM deployment it is centralized)
- Controller clustering (hitless failover) is not supported
- No Loadable Service Modules (you cannot upgrade parts of ArubaOS, you must upgrade all of it at one time)
- All controllers must have the same version (in an MM deployment this is not a requirement).
- Centralized Licensing does not support Licensing Pools if you use a 7000 controller as the master in 8.x
Long story short, go the MM route for the best scalability, performance and flexibility..