We updated the Rand GPS software (remove SD card from Xite unit, plug SD card into PC, run the Rand docker program on the PC)  and are pleased to report noticeable improvement.  The latency is down from 20 seconds (or total freeze of screen) to 1-2 seconds of latency.  Also, typing in addresses seems to work better–there is some latency, and the Rand database is still not as good as the Garmin database, but it is much better than what we started with. So new purchasers of a Winnebago with the Xite (Riverpark distributor) Rand McNally in-dash unit, I advise you run the update on the SD card as soon as you get the unit to improve your GPS performance.