depends what you're using it for. Spreading on bread? They're all good (better than any others i've found, sainsburys dairy free is just nasty)
Organic is the best all round, but is double the price. It tastes more like butter than the others, you can spread lots of it on bagels etc and enjoy the taste of it as well as thing you're putting it on.
Sunflower is pretty good for all things, has slightly less water content than organic so can be used for making toffee/caramel (the water in the organic one causes it to spit, and spitting boiling sugar is NOT good!). I use it mainly for cooking/baking.
Soya is pretty nasty. It's ok in sandwiches, but it does weird things to baking. At high temperatures it seperates out. Last time I made toffee and used it (for the first and last time!) i ended up with sugar syrup and slimey oil
. I guess they added soya to try and make it more creamy.
A few years ago when it was launched they gave out free little recipe booklets. They obviously make them for different things, because the recipes used different ones depending on type. They also now say on the side of the pack what their uses are. As far as baking goes, the best stuff you can buy is margerine, not the crappy 'spread' they sell these days (margerine mixed with buttermilk to make it more creamy/butterlike, i remember when i turned vvegan and thought i could have 'I can't beleive it's not butter', and when i checked the ingrediants I really couldn't beleive it wasn't, butter is a major ingrediant!). I guess that the sunflower is closest to what margerine used to be 15 years ago.