Limited slip rear differentials are best not only for muscle cars, but anywhere traction, or the power to overcome traction, can create wheel slip. These are mechanical systems that lock up when the difference in left and right drive wheels speeds exceeds a set limit, There are very handy in off road conditions as well. The system disengages over a set speed. Some off road enthusiasts prefer greater control over the locking action of the diff, thus the electronically switchable locker.
For casual off road fun and snowy/icy conditions, the automatic locking diff provides a nice boost in performance and kicks in when it's needed. No need to actively engage it.
One word of caution. Going around a corner with a locking diff in snowy/icy conditions can cause not just one, but both rear wheels to spin loose. This can cause the rear end to fishtail out. For some it's a surprise. To others, it's another way to steer the vehicle from behind.