Cooking Fruit Ice Cream

It's summer, it's hot and you are in the need of some ice cream!

I've noticed that in some fruit ice cream recipes, fresh fruit is pureed and added as is, whilst for some others, the fruit is simmered before blending and adding.

I'm generally more inclined to use the fruit as is for that fresh flavour and also to better retain the nutrients, but I can see the simmering step may have its purpose in concentrating and sweetening the flavour. What do you do? How should one identify the specific instances where using fresh is better and other cases where using cooked fruit is better?

Thanks everyone. :)