I don't know what the width difference is between those Holan's and the Givi Trekker Outback's, but can say that the Trekker's are infinitely better in every way to the Holan Nomada's (non Pro) I used to have
I had caribou cases on a 2003 bmw gs since 05, used them for sixty thousand miles. When I sold the beemer the guy didn't the cases. Got my S 10 had to buy new case mounts, me thinks they were givi rapid release. Had to drill new holes in the cases, I now have 30k on the S10, new setup for the givi mounts was around two hundred. Long story short close to 100k fifteen years and two bikes later and still no leaks! I saw a lot of bikes in Tennessee at the fall rally were sporting caribous. Would be my first choice again if I had to buy again.