I just went through this. I needed to get HD to my 2nd HD TV, 65 feet away. The sat box 2nd output was RF coax and SD only.
I first tried a wirless HDMI Rcvr/trans, this worked marginally, it would be fine and then no signal.
I sent that back and got a 65 foot 24 ga HDMI cable with booster built in, this came off ebay for $129 . Then I added a Rocketfish splitter and now I am happy.
Next I want to add 5.1 audio to the 2nd TV, I think it should work through the audio return on the TV going to a Home theater.
Hope this helps .