For that price range, I'd go for a Stihl 025 (MS250), new they're closer to $300. While I really love the 026, new it's more like $400.
From my real limited experience on a used one, and the experience of a bunch of hard users that I've talked to, I'd stay away from the Echos.
Don't know the price, and it's been a couple years ago now, but one tree company was having real good luch with the Komatsu Red Max top handle saw- although I'd stay away from top handle designs in general due much more kickback potential.
For a little less money, I was issued a Husky 141 for my work truck when I lived in TN. At first I resented such a cheap low-powered saw. It seems like I could always hear the scape of metal on metal when the chain was turning, but my oil was always almost all used up every time I was out of gas and I never had any abnormal wear. I always had plenty of power for the kind of jobs that you're talking about, and really no reason to complain (other than it had the habit of wrapping weeds around the sprocket when I got into brush). So I, after several gallons of gas thru it, I came to really appreciate it. It's around $200 or so new.