I had a recent case open with Dell, which was resolved satisfactorily by e-mail and a self repair by me.
I suspected some RAM had gone bad, which we eventually agreed was the case and I asked if the RAM modules could be sent direct to me rather than go to the trouble and expense sending the computer back to Dell for a warranty repair.
Dell agreed, the RAM arrived within two working days and since I replaced the two faulty modules I've had no more problems.
So yes, overall I've been satisfied with Dell's service experience. Put it this way, it is superior to anything HP can offer.
When I bought the computer it was provided with a free pick-up-and-return 2-year warranty on parts and labour, which was a major factor in deciding to buy the machine.