GG2,
Yes, there are some large cattle operations that are running Balancer and Simangus bulls. The Balancer sired females are bred to Simangus bulls, and vice versa.
A few of the benefits to this program are:
1. simplified crossbreeding program
2. easily able to maintain 1/2 Angus and 1/2 Continental genetics, which is a favored combination for many feedyards and packers
3. still maintain a significant amount of heterosis (both maternal and terminal heterosis)
4. many Balancers and Simangus are similar in structure, body size, etc. so which allows for producers to select for similar bulls of both breed types, resulting in more consistent calf crop than some other crossbreeding options
5. the Simangus/Balancer females are excellent mama cows for much of the Continental US (may need some ear further south).