Top speed on flat ground is 29mph, and I've had it for a little over a year. I couldn't venture a guess as to how many miles are on it.
I know some may think 29 is slow, but honestly, I'm comfortable with it. I run a 48t sprocket because I live on top of a huge hill. Anything less than 48t and I won't make it to the top, trust me, I've tried smaller sprockets.