We've always raised Limousine, and some have a good temperament, others do not. They get very long, but produce nice calves and nice lean meat. We've crossed them with herefords and angus. I've always personally preferred hereford. If any of your horses have cowsmarts you might want to watch for the horses chasing the cattle and stressing them out. Too much 'horsing' around can cause damage to fencing, structures and livestock. I catch my horses doing it now and then, after I holler at them, they quit.
*side note* Mixing livestock on pasture:
Horses can be mixed or rotated with other livestock to maximize the use of the pasture. If you run cattle and horses together, you do run the risk of aggressive horses chasing calves, or horned cattle going after meek horses, but more often there is no problem at all. If you rotate cattle with horses in a pasture, the bovines may clean up some of the mature grasses left behind by the equines. Since horses and cattle have different parasites, the life cycles of horse parasites will be broken during the time the cattle are in the pasture. Sheep, on the other hand, which tend to eat the center of a plant and leave the tall, tough outer leaves, don't really contribute to the health of a horse pasture. (Cherry Hills, Horse Keeping Almanac)