Rod Bearings Top & Bottom
Could be they are marked differently because they were built in different batches, Jan 2012 and Jan 2013.
The notches can be added, and should for a street motor. Given modern oils having lower anti-scuff package (ZDDP) levels, it's more important that the cam keeps wet, especially at lower RPM.
The notches went away with the magnum engine primarily for fuel economy and emission reasons. Reducing the amount of oil on the cylinder walls allows a lower tension ring package to be used. Less internal friction=better MPG. Also any oil passing the rings and getting into the chamber will end up in the catalyst causing it to overheat and melt down. The industry standard is 8-80 warranty on emission control equipment so it's worth the manufacturers while to make sure that spendy little bugger lasts through the warranty.