You would get a bigger benefit if you try to use Stabs outside of firepower slot. The slot gives it only a 3% increase which is pathetic compared to 20% it already gets. Aiming Unit would get considerably better in a firepower slot.
Just saying that PC Heavies were built different than Blitz. People complain about Heavies being heavily nerf in Blitz. In PC Heavies are literally annoying to deal with at times.