Let me get the same setup on a class 4 and class 10 SD card and test (I don't have the original 4GB SD card anymore - it was for someone else).
I did just test Primo 2.4 on a class 4 card with only 2 state maps on it and it started in 11 seconds (which is much faster than even my class 10 with all US and Canada maps/POIs/DEM, etc). So the number of map/poi files and dem, buildings, etc seem to slow down the loading significantly.
Will post comparisons between "fully loaded" class 4 and class 10 shortly (copying files over to class 4 card now).
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