So far, from what I heard and experienced, the best customer service among all laptop sellers is DELL.

I have 2 laptops, one is Toshiba and another is Dell.

For Toshiba, after using it for 3 years, its CMOS battery has been used up. I called up Teledynamic.
They passed my line from department to department acting like they didn't which department should be accountable for the task.
Just to get some information, I made 5 calls.
At last, they told me that they don't have the stock for my model.
But, they can order it for me. It takes 2 to 3 weeks to have the replacement unit to reach them.
It will takes another 3 to 4 days to replace the battery for me.
The most ridiculous part is they are going to charge me RM 1XX workmanship (forgot the exact amount) for changing a RM 60 battery in the case that I'm sending them myself the unit.

Now, using Dell.
So far so good.
If anything happens, just call them up.
The lady over the phone in a nice tone will ask me to hang up my call after getting my Service tags No.
She will call back to me immediately just to help me to save a few cents of my phone bills.
If the problems cannot be fixed over the phone, she will lodge a report and ask her technician comes to my place ( office or home, you decide ) to fix it for me.
The best part is the technician most likely will bring a new unit to my place and fix it before me.

This is most important if you have some things really personal and confidential stored in your laptop, I think you won't be sleep tight at night when your laptop is fixing in the factory while someone might browse through your personal data.

Thus far, I have made such call twice.
They came and replaced the motherboard twice and LCD once.
Even a minor problem like network card is not function properly due to loosen connection (sometime detected, sometime not detected), they will exchange the motherboard and network card at once.

Just on March, my Complete Cover warranty is due.
I'm very happy to extend it for another two years.
Now, I especially like to have my laptop run on raining and lightning days.
Of course, as long as all my important data is secured.