The RemoteRig system is far and away the best to do HF remote.
Look at my web site www.ky6n.com
and reviews on eham for the Remote Rig systems.
Sky Command is ok if all you want to do is stay on one or two freq's. and you are within range of your
base station. If you want to tune around and "work HF" you will find Sky Command is not the best way.
Remote Rig is an internet based system that I have used from all over the world.
Over the past 10 years I have remoted many types of HF radios using remote desktop software such as VNC etc. and used Skype for the audio. This works very well...but takes a computer at the remote end...pros and cons!
Overall, after 10 years and hundreds of hours and thousands of dollars ....the TS480 and Remote Rig is by far the best.