I love it. Cost $100 brand new. My lot is small though, probably less than 6,000 sq ft. Not sure if want to do any more than that. The blade is too narrow to do too much.
The big downside is that while it cuts grass really well, it does nothing to weeds. Any stem thicker than a blade of grass might as well be steel. So if you have a lot of dandelions or whatever, your results will suffer. This is the one I have:
katakowsj - I have the Fiskars. have had for five years. b_b is right - weeds'n'such require a weed whacker. I have a 7000-ish sqft lot and in general, when it's growing season, I hit the grass every week (30min). I hit the stubborn stuff every other week with a weed whacker. Go cordless. All my stuff is black'n'decker, and all of it has the same battery mount. There's something delightful about being able to mow the lawn and listen to an audiobook.