Which is better - 1 horse or 100 chickens? :)
It depends on your project, on how you use these sprites etc.
If these sprites serve the same purpose (for example all are buttons), have similar properties, behaviors, then it's better to keep them as 100 frames in one sprite object.
But there may be exceptions, for example if the images are big, one sprite with 100 frames will use a lot of memory. If you don't need all 100 of them on one layout, it would be better to use separate objects.