Having had a new Front O/S Brake assembly ( Disc, Caliper, Pads and connecting pipes etc) fitted in France exactly 1 year ago.There has been no fault with this and everything is working OK - Just returned from 2250 miles towing in France.Whilst talking to my local Nissan Service manager, he told me that Discs should only be fitted in PAIRS - i.e. O/s & N/s together !Is this fact, or is he trying to pull a fast one ?Advice please.