I think the tinned versions are still good as a food, but you should try and buy soups that come in pouches or that are fresh - sometimes the 'tin' has components that seep into the soup. Fresh soups are the best, the ones that come in plastic tubs. You can microwave these and so they are great to take into work! You can get a brand called Simply Organic from ASDA and they are really good. Pricey but well worth it, and a tub does two meals.
mk - if you have a knife and a cooking pan/pot - you can make it almost as easy - just takes minutes to chop the vegetables - and as cheaply as you can buy it - then you know about the nutritional value:)
Making your own is dead simple and loads cheaper than bought so-called "fresh soups" many of which have nasty additives to give them a longish shelf life. Best to make it in largish quantities and freeze the extra - you'll soon build up a collection of different varieties in your freezer.