Beautiful Setting: Fun Experience
We were there for a quick overnight, but we enjoyed the "experience." Staying in a hotel that's a throw back to the days of Hollywood grandeur was a unique, fun time for us. The room was your average room, with a unique decor (again, a nod to the days gone by). The bathroom is tiny, and our tub had peeling paint. 
We were "promised" fluffy bathrobes, but our room didn't have any. We were also promised upon booking our room that we would be on floors 3-5, but our room was on the 11th floor. Not that we really cared about that. Another "negative" if you can call it that, was we were promised "Club Access" which was complimentary cocktail hour fare, and breakfast in the morning. What they don't tell you until you arrive is that children may not partake in this, because it's set up for business travelers. My 10 year old didn't mind, but it would have been nice if everyone in my "party" had been able to enjoy the breakfast. 
What my daughter did enjoy was the pool, and we spent a good part of our brief visit at the Biltmore Health Club. I thought the lobby was breathtaking and the staff very courteous. 
The one BEWARE I will share with possible visitors: DO NOT STAY NEAR THE ELEVATORS. In fact, if you get to your room and find yourself close to the elevators, insist on another room. Your hotel room will offer you no sound buffering, and you'll hear the "ding" of the elevators all night long. Unfortunately for us, another guest on our floor (only a room or two away from ours), came into the hallway and was loud, drunk and banging on doors for several minutes, waking us up and putting a damper on the "relaxing" mood the hotel had created for us. I can't blame the Biltmore for that, but beware, you will hear everything going on in the hallway. Be sure to turn on the rooms A/C and it will drown out some of the noise - that's how we survived the night.
And lastly - while very courteous and helpful - the VALET service will run you $40 per night, so be prepared for the cost of parking in Los Angeles. I had done my research and expected it, but if it was a surprise I would have been bummed out. 
Overall, just 3 stars because of noise, and a few details the staff overlooked. On the positive side, it was neat to be able to show my daughter a bit of living history, in this grand looking hotel.