I have no issues on my two Macs with multiple accounts that use the same iCloud accounts - a rMBP and Mini Server.
I have 4 accounts on my rMBP, in fact - an Admin account, a work account, a "play" account that I'm using now, and an accounting/finance account. There's 2 accounts on my Server - an Admin and one work account.
Outside the scope of your questions, I also use 1Password and utilize the Shared folder with Default Folder X for moving documents from one account to another.
I turn on Find My Mac in the Admin account only, and sync other iCloud items across accounts as I see fit - for instance, I don't turn on Mail, Contacts, Photos, and Keychain in my "play" account as they're not needed in that account for what I use it for.
The only time I have issues is when Apple's iCloud services go down, but other than that I'm happy with the results.