MEGA Armored NOBZ are cool to model, and can be fun to play, I play tested a similar list and this is what I found
Negatives

Leadership- They can not take bosspoles , and are ld 7 and can not get a rerolll. It is sad to see a bunch of MANz getting wipped out after lossing CC.
Manuver -Also they are slow and purposeful, they quickest way to shape the battle is to kill thier transports( if any) and shoot the crap out of them as they make their way across to you.
CC- I am not 100% about this, but I beleive that they also will go last in CC due to thier powerklaws and that can lead to a lot of dead MANz.
Posatives

Fear Factor - Thay look so intinidating
Shooting- Twin linked is the only way to go
Fun factor- They are cool models to paint up and modify