So, I caught a Naive Pheromosa with 4 perfect IV’s. Perfect IV’s in Atk, SpAtk and Spd, but unfortunately I also got SpDef as well despite it being Spd+, SpDef -
Would it be worth keeping or would I have to find one with better IV’s in HP?
Getting a 4 IV Pokemon in the ultra warp ride is quite rare. Add to it the factor that it has perfect IVs in exactly the stats pheromosa is any good at and a perfect nature, you have an excellent Pokemon.
I recommend you use it all you need.
Still want a six IV pheromosa? Farm shards from poké pelago, and exchange it for bottle caps to hyper train your pheromosa!
Anyway, pheromosa is so exceedingly frail that it is OHKOed even with resisted hits, so there is really no point.
Use it as a mixed wallbreaker with a focus sash.
Hope my opinion helped!
I might keep it just in case, but you should probably try to find one that's better. If you cant, use the other as a last resort.