Found a treadmill on craigslist.
2011 Precor C956i. It has about 3000miles/1000 hours on it, and appears to be in decent shape.
Original asking price $550, now changed to $925 after contacted the seller.
http://www.fitnesssuperstore.com/Precor-c956-Treadmill-p/c956.htm
My wife and I are both runners. It will be used up to 40mpw, usually for easy running plus some workouts when necessary. With a 3.2hp motor & 12mph top speed would it handle sustained runs at 11mph. On a lesser brand i'd assume not, but i've heard good things about precor.
I live in the middle of nowhere and will have to drive a couple hours to look at anything. So I need to be pretty certain before I hop in the car. Most other commercial style treadmills on c-list are around $1200. This one seems like I should jump on it if I can get it for the original price of 550.
Any other generic buying advice welcome.