ww, I shot a 150 lb dressed whitetail with the 20 ga. Federal you are talking about that was facing me head on at 55 yards. The hour glass shaped projectile entered in the front brisket, 1/2 of the sabot entered with the slug and exited out the front shoulder and the slug was found lodged about 1 inch from exiting the rear ham. For lack off better words it almost went from front to back. The deer ran 150 yards and not a drop off blood. Luckily I saw the general direction and my buddy and I found the dead deer.
The slug was barely deformed, almost completely reloadable as you indicated. That said, those offerings from Federal are the most accurate rounds of any tried in my wifes 20 ga. rifled tracker. My 20 ga. rifled tracker doesn't do as well with any of the various rounds but is ok accuracy wise with Winchesters partition gold saboted rounds . I also am starting to use the Remington core-loktd. The ones I shot so far impact higher on the target and are about as accurate as the partition gold. The partition gold are great deer killers, as I have dropped most of the ones I shot with them right in their tracks, usually with good exit wounds that would leave a good blood trail..........Chainsaw