The sheer size of this place is impressive and might be part of their problem - they carry so much from home audio, to computer components and even kids toys. This place even has a cafeteria in the center????
Inventory is a clear issue here, on my three attempts to shop with them, I've only been lucky once in getting what I wanted. I do highly recommend doing their purchase ahead of time online instead of trekking out to the store, even if their inventory says they have it.
On two occasions I have ordered ahead of time only to be called a couple of hours later being told they were unable to find it and asked if I was interested in something else (I ended up cancelling the orders)
I prefer shopping at Amazon over them, but if you are hoping you are lucky enough to pick up something same day, it might be worth a try here (but again pre-order online and let them get back to you on whether they could find the item).
Service in store is hard to come by, but if you hunt you might find it.