If you are asking seriously:
One has guards/mark target/T3485/crew repairs depending on situation or play style the 120mm is the weakest part.
The other also has AT overwatch and the DSHKA, AT overwatch is strong enough to warrant the pick on its own and great mg back up by OP mortar pushes it to be a staple amongst most game modes.
The last one you probably hardly ever see as shocks are great but playstyle/map dependent and the arty is great against OKW but lack luster against OST unless there are arty/Pak43.
Yeah Guard Motor is just a great doc. Similar to OKW's Overwatch in the sense that more or less everything in it is quite good.