It all depends on which Garmin you have or what you buy - or want to buy. The new 7" 2757LM comes loaded with very detailed maps of Mexico - no chip needed - no downloaded needed - lifetime updates. It contains some pretty accurate maps of most towns we have been in. I have not done a complete comparison with Streets & Trips to see if one or the other contains more detailed maps. The both get their maps from Navteq so probably about the same. We just went to Mineral de Pozos a few days ago and looked for a town street map on both our systems and what they show is just a couple of un-named streets of the main highway. But they both show many other towns with accurate street by street info in pretty good detail. Much better than the chip we had in our old Garmin. New technology keeps moving.