If you have big construction jobs to do, or lots of plywood to cut, you might consider an in-line circular saw -- worm-drive or hypoid -- for more power and faster cutting. With the motor mounted behind the blade, worm-drive and hypoid circular saws are driven by oiled gears deliver more power than a sidewinder's side-mounted motor. Worm-drive saws need regular oil changes, but the newer hypoid saws have sealed gearboxes, with no oil changes needed.
Worm-drive and hypoid saws are heavier than sidewinders, so they're more tiring to use. However, the longer reach these saws provide is useful for cutting plywood and other sheet stock, as well as when reaching down to the floor or up overhead. This Old House notes that since the handle is further from the blade, you get a little more margin of safety from kickback. Also, most worm-drive saws come with convenient rafter hooks for hanging.
In tests of in-line saws at the Journal of Light Construction, the DeWalt DWS535 (Est. $180) leads the pack. This 7.25-inch, 15-amp worm-drive saw is lighter than most in-line saws at 13.8 pounds -- although that's still considerably heavier than a sidewinder. It has a bevel capacity of 53 degrees, with detents at 22.5 and 45 degrees, and a sturdy cast-magnesium foot plate that owners describe as very sturdy. Reviewer Tim Uhler calls the blade guard "exceptional," saying it never snagged even on the trickiest of compound cuts. He also really likes the saw's clearly marked bevel and depth guides and its reinforced cord, which resists damage from being jerked.
Both Uhler and owners at Amazon.com really like the accessories that come with the DWS535. For instance, its well-designed rafter hook is wide enough at the opening to slip over a 3-inch board, but then it narrows to fit over a standard 2-inch board. The optional DeWalt DWS5100 rip guide (Est. $45) also gets high marks for its generous proportions and sturdy build. A few users at Amazon.com report problems with sparking from the motor, but fortunately, DeWalt's 3-year warranty and 1-year service contract cover the damage.
The runner-up in Uhler's test is the Ridgid R32103 (Est. $175). Like the DeWalt, it has a 7.25-inch blade and a 15-amp motor, but at 14.9 pounds, it's significantly heavier. Uhler says this saw "handles and operates exactly the way an inline saw is supposed to" -- smoothly and powerfully, without any snags. Both Uhler and reviewers at HomeDepot.com appreciate the clearly marked bevel gauge, which adjusts easily up to 51.5 degrees. They also like the lighted plug, which glows when there's power going to the tool -- a feature owners say is a lot more useful than you'd expect. The one thing reviewers particularly dislike is the base plate, which many of them describe as flimsy. Both Uhler and some HomeDepot.com users say they've had problems with the shoe bending when the saw was dropped -- and users also mention some other mechanical problems that cropped up during the 3-year warranty period.
For those who really dislike changing the oil on a saw, the Makita 5377MG (Est. $180) is a hypoid saw that gets generally good reviews. Like the other saws in Uhler's test, it has a 7.25-inch blade and a 15-amp motor, and at 13.2 pounds, it's very light and compact for an in-line saw. Uhler also says its hypoid gears run "exceptionally smoothly." Both Uhler and reviewers at Amazon.com describe this saw as very ergonomic, with grips that fit nicely in the hand. However, Uhler complains that the blade guard tends to snag during compound miter cuts a problem most home users didn't encounter, but one that can be a serious annoyance for professionals. Owners also note that the blade kicks powerfully when it's started up, and they have some durability complaints, including bent base plates and having all the oil drain out of the supposedly sealed gear housing.