Cordless Weed Wacker

I'm sure this subject has probably been covered, but hey, why not relive the great moments of our past?

I'm looking into getting a new weed wacker. DH has a nifty gas powered one that I can't start and it kills my back to run (back problems for years). I figured I'd get a cheapo electric corded model because they are lightweight, DH is talking about getting a cordless rechargeable one for me. He buys me such nice things...weed wackers, vacuum cleaners, car washing tools, the list goes on! tee hee hee

I've searched the net and done some homework, but don't like the reviews I'm seeing on these. It looks like the cordless weed wackers may be lacking some power, is this true? I don't want to cut down saplings, but I do have some bad weedy spots.

I liked the looks of the Craftsman 24 v. 10 in. trimmer/edger http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=LAWN&cat=Power+Lawn+Equipment&subcat=Line+Trimmers&pid=07174805000
but reviews say it often dies in a year, lol!

Right now I'm leaning towards the Worx GT 18v. 10 in. trimmer/edger http://www.sears.com/sr/javasr/product.do?cat=Power+Lawn+Equipment&pid=07174022000&vertical=LAWN&subcat=Line+Trimmers&BV_UseBVCookie=Yes
for $15 bucks more the reviews seem much better, plus I like all the bells and whistles. Yes, I'm awful at taking out the flowers w/ the weed wacker and I love the idea of having that goofy little guard on it. The edger on this one looks sturdier also.

So, who uses what and loves/hates them and why? My biggest concerns is that it be lightweight and get the job done.

Thanks so much, can't wait for your responses!
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