Massive damned reply edit!*
i thought you said once that you need to spend at least £700 on a pair of speakers ? What's wrong with £300/£500 speakers, surely there are some good ones under £700
Damn laptop! Didnt see the whole reply - I still bet you my entire bike collection that you wouldnt be able to tell the difference between interconnects, including your own in a proper 'blind test' or A plus B plus X test (ABX)
If you want to discuss speakers, its basic economics, you will have better cabinet materials and drivers for your £700 over a £300 set. At £300 retail, you are looking at a manufacturing cost of around £55 per pair
whereas higher up the scale, a £700 set would have cost about £180/£220 per pair.
As for the physical sound of a speaker, its all in the design and material choice, different cone material will sound different same with cabinet materials, driver materials etc etc. Actual designs such as transmission line, closed cabinet, open/ closed baffle, etc etc.
And yes, there are many many good speakers at £300 but if you really want to do things properly, ditch the 200GS and go Deore DX/ XT (XTR is for the mad).
Another big fat edit*
lots of fun to be had here:
http://www.head-fi.org/t/486598/testing ... -and-myths