In my experience those digital hotel safes that you set a code for usually have a standard override code (often 5555) - failing that a sharp ta to the top of the keypad gets some open. It's a kind of a shame they don't take this sort of things seriously.
I don't trust them either. When I check into a hotel/motel; I ask for no maid service. I do ask for an extra set of linen though. They always look at me like I'm crazy. Even when I ask though, some establishments clean my room anyways? I can't prove it, but I feel I have had stuff stolen form my room. I just saw a commercial for a new Los Vegas hotel. Their sales pitch was we clean your room 2x daily. I said to myself, "I'm not going there." When I bring a few grand worth of stuff to a hotel, and decide to take a chance with the maid service, I lock my stuff up in a large Pac Safe made for Backpacks.