I pity the fool who don't use a GPS, sucka.
I have the Garmin Zumo 550 (purchased before my Lotus)
+ LOUD speaker for our car
+ bluetooth hands free calling
+ waterproof
+ speaks street names
+ you can put in your own POI, and Photo Radar alerts
+ you can use it on a motorcycle also
+ Garmin rocks
- it's bigger than a NUVI
- it's hard to secure in the Lotus due to size
- no speaker seems to be loud enough for our car (it was loud enough in my Miata
)