Pros: Not too heavy, comes with two batteries, easy to use, works to trim grass and whack serious weeds
Cons: Battery only lasts about 30 minutes for major weed/grass cutting
So in full disclosure, I don't have tons of experience in the string timmer/weed whacker area. I do know that my family has had a gasoline weed whacker up at our cabin. The problem was...we'd need to cut back the weeds for fire protection every summer. But we could never get the darn thing to work. And a tool does very little good when you can't work it (plus it was really too heavy for my mom or me to use it).
In comes the Black & Decker Grasshog Trimmer. First of all, it's electric. So you don't have to worry about spilling gas any where. It's really easy to use. Just charge the battery. Pop it in. Click the safety switch. Click the on switch. And you're chopping down some weeds! It's not too heavy so the weed whacking responsibilities can be shared.
When the battery is fully charged, it does a GREAT job. It's speedy, can cut the weeds down pretty low, keeps the grass from whacking in your face too much because it's got a safety guard (but you should still wear eye glasses). When the battery is fully charged....it's awesome. And it turns on in an instant, so you don't have to struggle with it at all.
The only problem is when the battery starts fading. The manual says that the battery lasts something like 3 or more hours. I was only able to get about 25-30 minutes worth of serious weed whacking done before the battery got too low. When it gets to a certain point, the string isn't going fast enough to cut the grass....it just sort of flattens it.
If the battery lasted a little longer, I'd give it more than 4 stars. Everything else is great. And it'd probably last longer if you're just trimming the edges of your lawn. But...if you're using it more like a lawn mower replacement, just know you'll be taking good long breaks in between your whacking. Other than that, I definitely recommend it.