err7 = lifter
I've had this treadmill (Endurance XT3i) since 2005 and it worked just fine until this year. Mind you though, that until this year (2012) it was being used primarily by an elderly woman going no faster than 1.0 mph with no incline. This year however, I have been logging about 5 hours a week on it, usually at an incline of 3 and speed between 4.4 and 6.0mph. A few month ago the lifter went out when I stopped the machine and it read "Err7", which means that the computer no longer recognizes that the lifter is in place.
The lifetime warranty is great and the replacement part was shipped out (at no cost) and the old part was then returned in the same box. The part was installed however the display then read "Err6". Tech support was called and all we had to do was unscrew the shaft a bit so that a few threads were visible and it worked just fine.
However a few months later that same part went out again. Perhaps the machine can't handle all the bouncing weight that comes with jogging or running. I still like the machine and its great for the price, and since the parts are covered the only downside is waiting for the replacement (a few days to a week).
The machine does come with a few pre-set modes, but they don't have multiple intensity levels so you still have to adjust them manually if they are too easy. (I find they are suited for a beginner). The distance and time displays are accurate and you can also set it to count down the time till the end of your workout. There is no heart rate monitor, though most are fairly inaccurate on machines anyway and if this is important to you I recommend buying a chest strap monitor.
I also find that the calorie counter is very inaccurate since it uses a generic algorithm without taking into account weight, height, gender, age, and heart rate. (again a good heart rate monitor would be helpful since you can usually enter in those stats and get a more accurate assessment on caloric burn).
The incline goes as high as 12 and max speed is 10.0mph. To stop the machine there is a large button that stops the belt at a more gradual and natural pace but for an immediate stop there is a magnetic key on a string that can be clipped to you so that if you fall or trip it detaches and the belt comes to a halt instead of throwing you.