I recently purchased a Sole F83 treadmill. I've been quite pleased with the F83. It lists at around $1,700 and generally gets very good reviews. It has a good warranty, a solid motor, and the deck is very stable. It feels like a well-built piece of equipment.
The only two complaints that come to mind for me are that (1) the incline is only in full degree increments; I'd prefer a little more granularity with the incline settings, and (2) the interval program changes the incline throughout the program, which doesn't make a lot of sense to me. I'd rather it just kept the incline the same and changed the speed so I could do speed training more easily.
A couple of additional nice features are that it has an audio-in jack for mp3 player or whatnot as well as built-in speakers. They're not high-end, but they're just fine for audio books or for motivational music. The console display is also very nice, with easily accessed speed controls. There are also speed and incline controls on the hand rails, which is a nice touch. It also folds, which can be a nice feature. The motor is 3.0 hp (if I recall correctly), and the deck is rated for 300+ pounds. It should be able to take a pretty good beating.
If ordering directly from Sole, I'd recommend getting the turnkey shipping/installation. The treadmill is nearly 300 pounds, and I've read lots of reports of folks having problems damaging some of the wires while assembling the treadmill. (I was also recovering from major surgery at the time, so there was no way I was going to be able to lift anything....)
Good luck with your treadmill search!
Don
"Don't fear moving slowly forward ... fear standing still" - Kathleen Harris
"Last is just the slowest winner." - C. Hunter Boyd