There's more to a plunge router than just the ability to quickly change cut depth. You also have to maintain cut depth with easy-to-reach locking levers. In addition, the motor must travel smoothly throughout the plunge action, and the depth-stop system and gauges must operate quickly and accurately.
Plunge Action Locking Levers. Because plunge cuts often are made with the router running, the plunge-locking mechanism must be within comfortable reach of the handles so you don't have to grope for it while operating and controlling the tool. The Bosch, Makita, and Porter-Cable plunge bases each use a spring-loaded locking lever, which works nicely. Releasing the lever automatically locks the motor in position for a constant and dependable cut depth. DeWalt's lever is not spring loaded and must be locked manually at each depth change. After routing a few miles of material with each tool, we still had a hard time getting used to this design, especially when we didn't lock the lever securely enough and the cut depth suddenly changed.
Motor Travel. Rough plunge action can allow the bit to bite too deeply or retract too much, which can damage the work piece. The smoothness of a router's plunge action is mainly influenced by the strength of the return spring. If the spring is too strong, the plunge action will be rough, if the spring is too weak, it can be difficult to draw the bit smoothly out of the work piece. The Porter-Cable's return spring is too strong and requires too much plunge pressure, making smooth plunge cuts difficult. The Makita's return spring is a little too weak and doesn't always draw the motor and bit completely out of the work. The return springs on both the DeWalt and Bosch routers work well.
Bit Change. If you're like us, you change router bits frequently for shaping beads, chamfers, dadoes, and rabbets. It's a lot faster to change bits on a tool that requires only one wrench to loosen the collet. Only the DeWalt router has a spindle lock on the collet that makes this possible. The other three tools use two opposing nuts on their collets, which requires two wrenches to switch bits. They work fine, but they're not as fast or easy to use as the DeWalt model.
Dust Control. Given the health effects of dust from some types of materials on jobsites these days, it's important to control dust whenever you can. Makita ships its plunge router with a plastic dust-port adapter that fits both bases, but DeWalt manufactures its tool with an integral, or "through the column," dust-collection system. The system includes a hose adapter and a specially designed router base, which really works. You don't need a special collar or fitting and can attach your vacuum hose right to the router itself. Bosch and Porter-Cable don't include dust collection options with their conversion kits.
Variable Speed and Soft Start
The Bosch, DeWalt, and Makita tools all have variable-speed and soft-start features. The Porter-Cable is single-speed and has no soft-start circuitry. For our work, variable-speed and soft-start motors are useful?if not critical. Large bits like those used for shaping raised panels should be run at slower speeds, which we can control with the variable-speed feature. Soft-start motors are easier on your wrists and result in fewer "hard-start" mishaps with your work. All three units with soft start and variable speeds worked equally well in this regard.
Plunge Configuration. In the plunge-base configuration, we found the Bosch router the most comfortable tool in the group. The large handles are easy to hold and the unit has a low center of gravity, enabling it to really hug the work. The Makita, Porter-Cable, and DeWalt tools are more top-heavy, each requiring a little additional hand pressure for a real sense of security on the work piece.
Fixed-Base Configuration. In the fixed-base configuration, DeWalt's router is a standout. It has a small, short motor and low center of gravity. Bosch is a close runner-up, with a wide base and large wooden knobs. The Porter-Cable and Makita feel a bit top heavy.
Switches and Levers. On the Bosch, DeWalt, and Makita units, all of the switches and levers are within easy reach. The Porter-Cable's side-mounted power switch is hard to find, though, largely because you adjust cut depth by rotating the motor. This relocates the switch with every adjustment, sometimes putting it out of sight, so you have to hunt for it.
The Makita motor swivels, too, but the power switch is located on top. You can reach the switch, but if you set the router upside down (as we do all the time with flat-topped routers) it's possible to accidentally engage the switch if you hit something like the corner of your work table and turn the tool on, which happened during testing. The Bosch and DeWalt switches are always in the same position because the motors don't rotate to control cut depth; they're near the handle and easy to reach.