The R11s is worth upgrading from the R11, it has a slightly lower trajectory which allows it to cut through the wind on long drives.
The extra forgiveness is like having a wider ding zone.
Missing the ding by 1 - 2 mm on either side doesn't affect its course.
For this reason alone, its worth the upgrade.
Far less drives off the fairway.
I wouldn't go back to the R11.
The extra 2 yards stated in the stats, over the R11, is the result of having the lower trajectory.