Ra/Su here.
I use Nemesis Shooter and Circuray (From when Level 2 Badges were dropping like crazy on july), i use Rare Drop Rate Tree, and HP Drink so i can take more hits. I just use Blight Bullet + Summoner Mark, Impact Slider and Shotgun Blast, then repeat. On the freaking cars, i just jump and use a PA that makes me rover or stay in the air, because those cars hit a lot.
But for the most part, i just dodge and use Impact Slider IFrames for dodging.
On PD, i start with Satellite cannon and Photon Blast, and when i need to move Impact Slider and the Shotgun blast PA (Diffusion Round).
I play safe (With HP Drink my Hp goes up a lot), and i can do it in 9 minutes. I think if i did go full Damage, i could manage 8 minutes, but i wish to play safe.
If i get damaged and i have time to heal, Megiverse or Resta is enough, but if i'm in a giant hurry, chugging down one monomate using the Mate Maniac ring helps a lot.
Remember: You only need less than 11 minutes to get an S rank on it, so it's not much of a problem if you don't want to rush killing it.
Remember 2: Summoner Sub does not have Auto-mate nor does it have Iron Will, so it's a lot more difficult if you are not accustomed to keeping an eye on your HP and healing fast.