User blog comment:SlashZero/Spring 2015 E-6 Hard Boss Pre-final & Farming Composition/@comment-26130473-20150511152207/@comment-861160-20150512055549

It doesn't reaaally matter as it will often get wrecked to the point it won't matter at the preboss. I'd go with whatever you have that's better for the shelling phase, although if you want to bank on good RNG for it not getting shot down Ryuusei (601st) or Tomonaga Tenzan is okay I guess.