Here's a link to a comparison of our CNET reviews:
http://reviews.cnet.com/4504-3430_7-0.html?id=32078943&id=31789579
It appears the C550 is heavier, and specifically designed for driving in North America, where the Nuvi 660 could be used in Europe as well as used for walking.
Garmin Nuvi 660 and Garmin street pilot c550 which is better? I know Nuvi 660 has a bigger screen than c550, but apart from that what are the differences and which one I should buy?
bristi

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