Microwarpdrives provide a flat 500% to 520% speed boost. Microwarpdrives fit into a Mid-slot and scale with ship classes: 5MN for Frigate-class, 50MN for Cruiser-class and 500MN for Battleship-class ships. Compared with High Speed Maneuvering I at a minimum.
Microwarpdrives can now be used in complexes due to changes introduced in the Apocrypha patch.
1MN Microwarpdrives can be easily made cap stable on most frigate setups. Large MWDs most often make a ship cap unstable when active.
The MWD trick can be used to allow any ship with an MWD to align in 10-12 seconds, even heavy battleships that normally take much longer.
After giving the warp command, activate your MWD and then click it again to deactivate it. Activating the MWD causes your agility to go down a bit, but your top speed also increases dramatically; your ship will continue to accelerate for warp based on your new top speed. After ten seconds, your MWD will shut off and your ship's top speed will drop accordingly; however, your ship's current speed will be much faster than the 75% of base top speed necessary to enter warp, so you will enter warp as soon as the MWD shuts off.
This only works when you are warping from a dead stop (i.e. after jumping through a gate); the agility hit will often increase your align time significantly if you try this trick while moving.