I'm using the Activities mode of the Harmony, so it sends the "Turn On" code when I select "Watch Dish" and the "Turn Off" code if I power down or switch to another Activity. The problem with Toggle Power is it does exactly that. If the Dish Receiver is already On, I don't want to turn it off if I press "Watch Dish".
That's why I have this Harmony, BTW. I had given it to my in-Laws for Christmas many years back but the FIOS DVR they had did not have discrete power commands, just a power toggle, so the Harmony remote would sometimes get out of synch, requiring my Father-in-Law to grab the FIOS remote to turn the DVR back on. He appreciated the gift, but using it was actually more frustrating than using the DVR's remote to control everything. It sat in its box for five years until my Harmony 880 stopped charging because the gold wore off the charging contacts. The Harmony (forget the model number right now) has a magnet to insure good contact between the remote and the charging base.