better in most situations then the MT/R
The MT/R is made for one thing, and one thing only: Offroad capability. Everything else comes second for that tire.
This new "Silent Armor" tires appear to be a streetable, light truck tire, similiar to their regular Wrangler tire, but with beefed up sidewalls so it won't tear up quite as easily as the regular Wrangler.
The two tires are in completely different leagues/categories. Don't compare them; they are made for two completely different purposes.
edit:
More information, from the link you posted:
This rating scale can help you to compare two or more tires within each category. However, using this scale to distinguish between tires across different type of categories would be misleading.
Granted, they are both a "light truck tire", but they are not in the same category; The Wrangler Silent Armor's are a general light truck tire. The MT/R is an offroad tire.