Gas-powered hedge trimmers with good ratings from ConsumerSearch.com include the Husqvarna 122HD45 and the Poulan Pro PP2822. The Husqvarna cuts powerfully, the exhaust vents away from the user, and the model is fairly easy to handle. The Poulan has a rotating handle that helps users reach tight or awkward spaces.
Gas-powered trimmers leave cleaner cuts and lines than electric trimmers, and they are able to handle thicker branches as well. Their power and speed make them useful for quickly trimming a large amount of hedges. However, they are louder than electric trimmers and tend to weigh more; additionally, the exhaust may irritate some people.