For developers 99% of the time they just want to see what queries are running on the database and if there are blocking sessions. Sometimes I've set up a oem user for specific db's but most of them stop using it if I also present a user that can query the above. Some then set up a web page or just query via toad. I do have separate accounts for SA's that can see the hosts and ASM. They get the alerts for host issues and ASM as well as dba's. I find it helpful as they usually use different toolsets for monitoring and it's good to have the same screen to look at in diagnosing performance problems. I know a group whose manager had a oem dashboard always going on the monitor and sending out emails for every little thing. The job then became managing the manager.