Hi, I'm survey on a mobile workstation laptop for office, which model /series I should go?

Requirement:
1) Enable display 3 displays individual at the same time with/without docking station.
(Monitor display itself + 2 external monitors)
2) mid-end GPU or high-end GPU with HDMI/DisplayPort out on laptop.
3) 15" monitor

Website link please if any.

a) XPS
b) Precision
c) Inspiron

How about Alienware series, which come with GTX GPU, can support 3 monitors?
If can, must with docking? (If Alienware available for docking?)

Hi, I'm new in Dell laptop and I'm looking for 1 unit which:
i) come with docking station
ii) can support external display up to 3 monitors (24"-27")
iii) SATA + SSD both together

Well, is XPS sereis can meet my above requirements?
Or other DeLL series that have my above requirements?