It's time for Garmin to refresh its lineup and flood the market with a slew of dash-mounted GPS devices. In total there are six new series of navigators, with countless models scattered amongst them. The "essential" nüvi 30, 40 and 50 (top left) lines come in three sizes: 3.5-inch, 4.3-inch, and 5-inch sizes (we're sure you can guess which is which), and cover all the basics including a lifetime's worth of free map updates. Stepping up a notch to the "advanced" 2405 (top right) and 2505 series (4.3-inch and 5-inch lines respectively) nets you Garmin's Guidance 2.0 system. The software includes nic
