This is quite poor, I’ve got a Dell Studio 1749 which is around 20 months old now. I too paid a good amount of money for it and purchased the next business day onsite warranty and never had any problems with them.
My laptops power button totally collapsed into the casing 14 months into me owning the laptop, which is also where the screen is located, I rang dell technical support and next day they arrived at my place of work with parts and repaired the whole laptop right in front of me.
Few weeks ago the charge indicator light on the side where you put the power lead in failed to stay on, again Dell arrived next day and replaced pretty much the entire machine.
They also sent me a replacement 130w power supply to replace the 90w supply that overheated fair too much for my liking and allowed me to keep the old one.
I’ve got nothing but good things to say about Dells next business day onsite warranty. Really surprised to read such an awful report of poor support.
Glad you get this sorted, guess you had to keep on at them like recommended in this thread.