I bought the 2012 Navtek update and installed it about a week ago. I thought I'd post my impressions of its value for others to consider.
I live in Ottawa Canada and the previous maps were frankly lousy. Many area's of the city, built within the last 5 year were not accurate or even included. Rural areas close to the city were patchy including only major roads. POI were very thin with few restaurants and even the major museums and national sights missing.
I thought the 2012 upgrade would be a dramatic improvement. It was a disappointment. Urban maps and near by country side is marginally improved but still lacking (see below), rural Quebec is still non existent. POI's are better but a free app on my phone is far more comprehensive.
For comparison I have a Garmin Nuvi 50 I bought for my wife's car. It cost about the same as the upgrade $120. It is far more accurate and complete and includes an astonishing database of POI. On a recent trip from Ottawa to Washington virtually everything I could find on yelp or tripAdvisor or Google was already in the POI. If I had to guess I'd say map wise the navtek upgrade is not more than 80% of the garmin and poi wise not even 30% of th Garmin.
At $20 the Navtek upgrade might be worth it at $120 it's a cruel joke.