The combination of Viral, Heat, and Slash is ridiculously effective, and with this build, it's easy to switch out the Viral for Magnetic to go against the Corpus. Heat may not be as effective against the Corpus as it is against the Infested or Grineer, but it still does reasonably well. The Corpus are comparatively squishy anyway, as long as the Magnetic procs are there to demolish their shields. As always, [Primed Point Blank] can be traded out for a Primed faction damage mod, if you want to bother with that.

The difference for me on Shotgun builds is whether they need added fire rate or not. This gun honestly doesn't. So I'd go with Heat.