Jokes aside, it is very disappointed that the unit seems does not support sdhc format, could be lack of driver since other device (P3600) seems fine with a mod rom. In addtion, with microSD, the media throughput speed is very low compared to those high performance SD card. For example, the Sandisk sdhc 4G microSD card only has class 2 rating (2 MB/s) vs 6 - 10 MB/s common in high performance SD. The overall unit performance will suffer when you install program to the storage card. TomTom for one is very picky on the read speed of the map: someone tested on a cross country route calculation and a good high speed card with no name one, less than 2 min vs over 30 min.