Hoist,
You could get by with the older version provided Joe is not going to run your bike in closed loop mode at all. Wes/Chuck didn't on mine so I would suspect the same on your bike. There were some issue fixed with talking to older ECM's / softail I think was what I was told as well as what was said above about the Closed Loop Bias on each cylinder and they added some more maps.
For Beerman I would suggest getting the latest software as it has the ability to do the closed loop bias on both cylinders and will allow them to tune the rear cylinder separately from the front especially when in traffic / cruise for saving gas if he stays in the closed loop mode.
Here is the exact changes from the oem calibration file. Although they don't tell you everything spelled out.
Model Year 2008 Software Updates
(CD Revision L, 7/15/2007)
• Added Model Year 2008 calibrations and parts lists numbered 96 - 107.
• Added column for 2008 Touring ECM.
• Corrected parts listings for calibrations 73, 77, 83.
• Corrected model year for calibration 19.
• All but two 159 cals have been updated to either 171 or 176.
• Removed HDI cals 89, 90, 91. Replaced by 'All Market' cals.