Just FYI trying to convert 68Gb of tiffs covering roughly 150 miles by 50 miles of the Colorado Front Range (or likely anywhere) will crash Geoconvert... Working on a script to chew through my 450 tiffs one at a time, creating the tmc and batchfile and running each one piece by piece..
Also built a script to pull down the USGS 1m NAIP imagery state by state based on year... might try to merge scripts so that it downloads/processes for coordinates and converts each image in turn.
The idea would be to just create the whole united states as i have the bandwidth to pull and convert.. heck if i do it right i dont even need to store the jp2s/tifs