I am currently riding coast to coast on a recumbent bike (US). The model that I am useing is a Bike E. That was the first recumbent bike I have experienced. Yes, The hills sometimes are monsterous, Of course I'm pulling about 60-75 lbs behind me with a Burley Trailer. All in all, the miles i'm getting are the same as a regular "pedels beneath the buttocks type". I have had some modifications added (larger crank).
Don't buy one if you don't mind people stopping you, and asking about the bike, they will. I had one women follow me to my apt. to ask where to but one. That freaked me out.