Can echo comments made on an earlier thread by Gary T and Marchesini. Have just had my S4 serviced at Dave Robinson's Wandsworth Town. Very helpful bloke, a lot cheaper than DLS/DLC and open each night until 9pm! Extremely handy, as he's only 15 minutes on the train from Waterloo.
Dave Robinson
360 Old York Road
Wandsworth
SW18.
020 8871 0503
www.ducatibikes.co.uk