I have the Samsung F3 and I'm very happy with it.
The Quadro 2000 is fine but I would suggest checking out the AMD Firepro V5900, which costs around the same as Quadro 2000 and seems to keep up with the more expensive Quadro 4000 at AutoCAD 2013 (Bench link: http://www.tomshardware.com/reviews/firepro-w8000-w9000...)
Also consider getting an SSD and maybe a case that has some noise dampening qualities such as the Fractal Design Define R3 / R4
The guy I'm building for works professionally in CAD and has already decided that the Quadro is the right card for his applications.
@Doron - Thanks for the input, Fractal design cases look stunning but are an extra £30 or so. Is anyone else doing cheaper quiet cases?
(I have an Antec P182 and it's amazingly quiet, not sure whether the builder will want to splash out on it though...)
@Metal Orient - thanks for the heads up on better prices.
@JMSellars - wonder if I could save a bit on the GPU (though dabs) and then put the difference towards replacing that 500Gb HDD with a small SSD. Will look into it.
Edit: Have updated above post to include Samsung 830 128Gb and reflect better price of Quadro 2000.