Yep, Both History Channels are great. Discovery is OK, and TLC has gone to crap with all the estrogen charged crap it's running now. "Discovery Times" channel has become an ultra liberal propaganda channel (what do you expect? It's run by the NY Times) but thankfully Discovery Science still remains somewhat objective.
The bummer is that Discovery HD still doesn't have much material to show, so it shows the same stuff over and over again. It's latest series, "Arctic Mission" has been beautiful to watch, but far too much fanatical enviro-nut propaganda to stomach.