Ideally I would like a set to build a kitchen around. Knives and the most vital and commonly used utensils. The best kit relative to it's price, and not leaving out important things like varied spatulas, whisks, spoons and other vital implements. Basically everything except cookware.
Similar post What knives are "required" for a serious home kitchen?
As knife sets available/affordable with vary from region to region, from year to year, and from wallet-size to wallet-size, I think it'd be best to answer this is a general fashion. I have worked as a chef in the past in a restaurant where we were expected to bring our own knives, although generally the one thing we were expected to bring ourselves was a long (20-25cm), broad-bladed, chef's knife. I am by no means the most experienced on this topic, but having expanded on my own knife collection in the past I can add my own real-world advice.
Firstly, you probably want to choose a brand. I do like the look of the global knives, but don't personally think they're good value for money. There are other brands out there, but there's a good comparison of 20cm chef's knives here: http://www.cookingforengineers.com/article/129/Chefs-Knives-Rated
If you are buying for a kitchen, I wouldn't get a bagged/cased set unless you want to keep them hidden in a drawer/cupboard. A bag or case is for carrying from place to place, IMHO. It may be cheaper than a set with a fancy rack, so I suppose you could combine it with a magnetic knife rack, but from my experience it's a bit too easy to knock knives off these... Probably not a good idea if there are small kids around. If there are small kids around, super-sharp knives are probably best kept hidden somewhere out of the way.
Secondly, I'd think about what you use your knives for. I expect most sets will contain a main 20cm chef's knife, a shorter filleting knife, and an even smaller pairing knife. If you bake or buy whole loaves, you'll probably want & find everyday use for a bread knife to do your crusty creations justice. I own a tomato knife and I find I use it a lot, tomato knives are also useful for other delicate vegetables where you may want to disturb the flesh as little as possible (I use mine for finely dicing red onion for salads, I find it easier to keep everything uniform than when using my other knives).
From there I'd consider what you cook and what other knives you may want to add to the set. If you're partial to a roast more than once a year, and haven't succumbed to the temptation of an electric carving knife, a matching carving knife and fork might be tempting. If you eat a lot of cheese, you might find a cheese knife a useful addition, etc.
