My speculation:
I don't see any reason why the LR version would perform significantly different on game than the original AB. The outside shape is different but it's still a bonded bullet. I would expect it to be a little softer in front with thinner front jacket than the regular AB to expand at the lower velocity threshold of LR shooting. From what I've seen of recovered AB bullets, they seem to retain 60-80% weight and perform like a Partition.
At this point, I would put my money on the ABLR performing better in game than the Berger hunting versions, across the velocity spectrum.
I concur with your speculation, but won't know until I actually get to kill something with a few!!
