We have stayed concierge at the DL and the Paradise Pier. The recommendation for Paradise Pier is ... don't do it ...it isn't worth the extra money. And, we probably won't stay there again. It wasn't a pleasant experience, all around.
We stayed at the DL concierge and it was nice. I don't think the offerings are as extensive as WDW, though. In the AM at the DL we had a couple different kinds of juices, milk, cereal, bagels, cream cheese and some small danish as well as some fruit. During they day they had pretzels, goldfish and cookies out as well as some apples and oranges. In the evening they have wine (not sure about beer) and cheese crackers, vegetables, dips, cookies (i think) but it wasn't as substantial as I have heard about being offered at WDW concierge's. The lounge is nice, though. Has a view of downtown disney on the 11th floor of the sierra tower. You can watch the fireworks from the lounge. They turn off the lights and pipe in the music. It is very enjoyable. It is open until 10pm which is much longer than at Paradise which closed at 8am. They have pop, juice and water available all day long. They ask you not take more than two cans at a time out of the lounge. Staff were friendly and helpful. If you stay, be sure to request the sierra tower as it is where the lounge is located. Otherwise you can end up in one of the other two towers and it isn't as convenient. The lounge is on the 11th floor. We stayed on the 10th floor and it wasn't bad. Rooms are not as large as those in WDW, though. But, they are nice and just rennovated.
Haven't stayed at the Grand Californian...perhaps someone else can help there.