To be fair the £199 vostro is closer in spec to what you've put together on Scan. That shipping though - WTF?
I was looking at this base units on Scan but the best I could come up with was £150 to 200 with no keyboard, mouse or monitor which is what put me onto the vostro. FWIW I recently bought a Dell laptop for a relative and it was surprisingly free of crap (though I did uninstall works and install open office).