The difference between SD and HD is significant for us but it's equipment dependent. With a HD receiver and a HD program go to Settings and change to SD channels only and then decide what is right for you.
On our used rig with a in-motion DTV dish we used it exactly once while driving to see if it worked and it worked very well.
So we were going to compromise with SD programming and the rig's HD TV. And then in central OR we could not get SD to watch the Olympics and our in-motion dish was SD only. This is not the only area that has DTV SD only. So we opted for a HD dish full array non in-motion dish.
And now there is one reasonable report that DTV will drop SD in about 2019. That would not surprise me at all.
