No worries Peter. it depends on the laptop but the Defiance and Octane have four RAM slots, some other do as well I think. It is simple to add, just take the back off and the RAM slots are visible. Unlike some PC sellers, PCS do not void the warranty if you open it up, so unless you break anything you can look around inside and add things without penalty.
That's very good of them - I think I'm going to go with the Defiance 17.3" and a 970M Graphics Card - I'm going to buy it in the New Year when I'll have a little more savings [ if I can get through Christmas ! ] so I can have the best specs I can afford - it's coming to £1327-00 at the moment with 500GB SSD and the 750GB WD Slim Blue so a little more money is required .
The problem I have is choosing whether to have 2 Drives and how to spread them about - eg do I go 240GB SSD for the first Drive with 1TB in the 2nd or give myself more oomph with 500GB SSD in the 1st and 750GB in the 2nd - do I need two Drives ? And what about the M/Satas ?