I'd like someone to provide a comprehensive list of the best item/pokemon combination (for instance celesteela and fini can be listed together as the best leftovers users,ecc.).
I'm mostly interested in good aguav/figy and sitrus berry users.
As of right now, pinch berries (50% percent berries, Iapapa/Wiki/Figy berry, you get what I mean) are the "go-to" item if you don't knkw what item you really wanna use. That's because this format is a bit more defensive and bulky (compared to VGC 16). You'll see in a second why I explained this.
In theory, in order to say Leftovers (6% recovery each turn) > Pinch berry (50% when you are under 25% hp), the Pokemon holding leftovers has to stay on the field for at least 9 turns (9 × 6 = 54% > 50%) so that holding leftovers is worth it.
Thing is, that's not easy, because even if this format is defensive, double battles are fast-paced by nature. It's unlikely that your Pokemon will stay for 9 turns on the field every game.
Point is, pinch berries "bypassing" item clause let's you use it on pretty much every bulky pokemon you use. So what are some great pinch berries users? Anything that is somewhat bulky can run a pinch berry. Joshua Lorcy just got 2nd place at Toronto Regionals using a Wiki Berry bulky Xurkitree.
In conclusion, a great pinch berry user is any Pokemon that you want to make bulky. Right now Arcanine, Fin, Snorlax are great pinch berry users but not because they are the best Pokemon holding that item, it's due to them being among the best Pokemon in the format.
Hope I explained myself well enough haha