Quote Originally Posted by principecarlo View Post
Basemap 5.01 is only 49MB (approx), yet 2.00 is 101MB (approx). Does one really need to replace a more detailed map with a less detailed one?
One doesn't need too at all. V2.00 predated V5.01 by almost 4 years [06.06.2007 vs. 14.03.2011], which is really of no great concern because highways change little in that time and DEM changes not at all [we'd hope anyway]. The presumption of less detail is reasonable on the surface because of the smaller file size, but rather than necessarily being less-detailed, V5.01 has been far more compressed by the mapmakers thus saving over 50 MiB of space on the unit. But most relevantly because all 3590 worldwide had V5.01 as OEM from the factory anyway afaik. V2.00 was OEM for much earlier units [2x5W for example]. Either can be used, but a more compressed map may make earlier units 'laggy' whereas later units such as 3590 can handle it because of enhanced processing capacity. Having said that, 3590 can use virtually any basemap including V2 WW DEM or an even earlier regional non-DEM one such as Atlantic from nuvi 2x0/3x0/6x0.