I saw the Civic Mugen-R at Croft a few weeks ago, All I could see was a few nice touches such as lightweight wheels, better brakes and an extra 30bhp.
But for £35k+ all you get is an awful interior, very hard suspension, rubbish stereo, no extras etc.... In my opinion you would expect more for the price tag than a front wheel drive naturally aspirated 4 cylinder engine with less torque than most 1.4 diesel engines that needs to be driven exremely hard to get any reasonable power.