The people best qualified to answer that question are the astronauts who've operated on ham radio from the International Space Station. Some weeks ago, I saw people talking about a video made by Col. Doug Wheelock, KF5BOC who was a very enthusiastic operator of NA1SS from the International Space Station. I had a chance to see the video today. It's fascinating on all sorts of levels!
During the video you'll see the inside of the ISS and be able to hear what it sounds like to operate from the International Space Station.
I particularly love the segment where Doug talks to the station near Houston and offers to come over and give a talk to the club. Wow!!!