The purpose of the ABI and MSG 1.61um channel is to detect daytime clouds and snow.  The MSG 1.61um band has a wider bandwidth than the ABI 1.61um band.  Below is a difference image of the two channels along with a histogram.

The above image is the difference image of the 1.61um ABI and MSG.  (ABI 1.61um - MSG 1.61um.)

The histogram shows the differences between the images are quite small.  Maximum differences are on the order of ~0.2 or 10 times smaller than the differences between the ABI 0.86um and MSG 0.80um.