You could buy several top-notch benchtop planers for the price of one 15" machine. Here are three good reasons to trade up:
1. More power: Benchtop planers have universal motors, same as a router or circular saw. They draw high amperage on 110 volts, run hot and, for these reasons, will not last forever. They’re also noisy, in case your family, neighbors or eardrums haven’t reminded you lately. In contrast, these 15" planers have 3 HP, totally enclosed, fan-cooled induction motors, like a cabinet saw. An induction motor provides quieter, continuous horsepower instead of bursts of peak horsepower. Since it operates on 220 volts, it draws about half the amperage of your benchtop planer, so you can actually plane down 500 or 1,000 board feet of hard maple without the motor glowing red. A bigger power plant will also allow you to take deeper bites to reduce stock thickness more quickly. These motors are made to operate all day, every day, to industrial standards.
2. More metal: Your benchtop planer weighs 100 pounds or less. At roughly four to five times that weight, these 15" planers are loaded with cast-iron and steel where it really counts. The head and column base castings, bed and support tables (in most cases) are all iron. Posts, cutterhead, gearing and bearings are oversized and made for demanding use. That heavy metal dampens vibration and keeps the planer bed properly aligned regardless of where you set it or how heavy the stock is that passes over it. Your benchtop planer has similar components in much smaller and more delicate scale, but it doesn’t hold a candle to the robustness of a production quality machine.
3. More capacity for the big stuff: Sure, a 15" planer adds a couple more inches of planing width, but think of capacity in broader terms. These test machines provide around four feet of combined bed length, so they’ll support long stock better. And, their mass allows you to feed in heavy planks without fear of tipping the machine over, like your benchtop planer might. Surfacing long, wide or heavy stock is simply not a problem here.