Having shopped online with other major supermarkets, Tesco, Sainsburys and Asda, I can say beyond a doubt that Ocado offer a far superior service. With the other supermarkets it is always touch and go if there are going to be missing items or substitutions. In fact one order from one of them contained 30 per cent missing items, 30 per cent substitutions so I only received 40 per cent of what I originally ordered. It is extremely rare for there to be a substitution from Ocado. The quality of the fresh products is consistently high and if there are any problems like breakages, which are rare, the refund method is very quick and easy. The drivers are always courteous too.