Although the top cordless hedge trimmers are now comparable to gas models in overall power, gas-powered trimmers still cut through thick branches more easily. They're also a very good bet if you're concerned about leaving the cleanest looking cuts and lines possible -- and if you have a lot of acreage to cover quickly; users say dealing with a gas trimmer's exhaust and noise levels can be a reasonable trade-off for that power and speed.
Among the best-reviewed gas trimmers, the Husqvarna 122HD45 (Est. $250) stands out as top of the line. Its 21.7 cc motor and 18-inch blade cut so powerfully that one Amazon.com user reports she can use it to take down anything short of a 2-inch limb, no problem. (The recommended cut capacity is just 4/5 inch.)
Like all gas trimmers, the Husqvarna 122HD45 is noisy -- but at just over 10 pounds it's still relatively easy to move around, and owners love that the exhaust vents to the front, away from you. The start sequence is also relatively simple, and anti-vibration dampers make the whole thing easier to handle. Meanwhile, the cuts are clean and straight -- the epitome of what you should look for in a gas trimmer.
The only consistent complaint we found about the Husqvarna 122HD45 is that the fuel line falls apart easily -- possibly a quality-control issue, since most of the complaints are focused in late 2013 and early 2014. Until the fuel line issue is resolved, we recommend making sure there's a service center nearby that can handle any necessary warranty service.
If you'd like an alternative to the Husqvarna 122HD45, the Poulan Pro PP2822 (Est. $190) doesn't have the same problem with its fuel lines, although its blades tend to be on the fragile side -- a problem you can sidestep by being careful not to tackle hardened, woody branches. Users say the Poulan Pro PP2822 does best with branches a half-inch or less in diameter, a little less than its advertised 3/4-inch capacity -- but it leaves nothing but clean, crisp cuts in its wake.
Users also love the Poulan Pro's rotating handle, which adjusts to 45 or 90 degrees to make getting into tight, awkward spaces easier. Downsides are its weight -- 15.8 pounds, which is manageable at waist level but tiring if you have to hold it higher -- and an exhaust that blows directly back at right-handed users. If you're capable of using it left-handed (so the exhaust blows to the left side of your body), owners say the Poulan Pro PP2822 is still an excellent power trimmer.