Okay, so... you can chop their legs off, which makes them unable to do anything for a short time before they automatically gain them back... you can chop their head off, which makes them unable to lock onto you until they get it back... and you can chop their backpacks off, which makes them unable to boost anywhere until they get it back...
And I just failed my first mission. ._.
Had to defend a "data probe" from enemies, but failed. Saw a TV version Gundam Heavyarms in the reinforcements before I failed, though... wonder if it's a hint that we're going to be getting modern HG Gundam Wing models soon, seeing as the only "HG" kit Heavyarms got was the Endless Waltz version back in the 90s...