I got a horizon ex-78 w/incline and it had issues where when you got to 5.0 mph the speed would show 2.4. I was not fixable. They finally sent me out a AFG 4.0. I really like the AFG 4.0
Livestrong is also made by a division of Horizon. I've seen the models at Dicks. They are very simular to the Horizon ex-78. If you go with the Livestrong make them plug it in and get it up to 5.0 mph and make sure the speed display does not drop down to 1/2 the speed.
Get one with the heaviest flywheel you can afford. It makes a difference. Sole, Vision, Precor, AFG, Spirit - all of these are good choices.