Guts isn't used as much in the OU meta, but Swellow and other Pokemon love to abuse Toxic Orb with STAB Facade for extreme results. I will say, however, that there is one Pokemon who loves to make use of that ability and that would be Conkeldurr, who gets Guts naturally. Assault Vest Conk with Knock Off is one of the biggest threats right now being able to shut down Pokemon by taking their items and dealing heavy damage with STAB Drain Punches. It gets even stronger when it can absorb a Will-o-Wisp or a Toxic for your team and completely flip the table on your opponent.
Conkeldurr @ Assault Vest
EVs: 252 HP / 252 Atk / 4 SDef
I've explained Knock Off and Drain Punch already, but Mach Punch is for a good STAB priority hit and Ice Punch can nail Gliscor and Landorus.
Pokemon who get Guts.