It's a nice place. As a Diamond I also get a $5 coupon there for the pantry. But...
No upgrades - all the rooms are the same
Wireless is spotty - I always ask for a room with a wired connection
Parking is a hassle - Right now is slow season but a few weeks ago it was nuts.
Anaheim occupancy tax - 13% or so...
The Hampton Inn across the parking lot gives Diamonds upgrades to a two room suite.
I've been doing the Hampton Inn in Buena Park and <gasp> paying the few extra bucks for the suite (even though I am Diamond). The savings in taxes pays for the guaranteed suite.