I've seen some really good Mo Betters but personal experience hasn't been the greatest.
Our first Mo Better calf is now 2.5 years old & raising an awesome bull calf. This cow was a clean fronted, deep bodied, great profiling heifer but when you viewed her from behind, she was one of the narrowest heifers I'd seen. We kept her but didn't show her. She never got much thickness until last fall & then by this spring as a heavy bred, she was good enough that we bred several back to Mo Better. She was out of a first calf ex-show heifer & maybe that had something to do with it. Her mom has a Mama's Boy bull calf this year and he is thick as can be.