>>48517537I've written up a guide about this before when the level 30 item enhancers first came out. Basically:
HP giving stat increases are great for laning phase bulk: This makes Buddy Barrier and Score Shield great choices for the level 30 item enhancers
Percent-based stat increases like Muscle Band, Scope Lens, Razor Claw, Energy Amplifier: These are more niche items but I prefer Muscle Band and Scope Lens.
I personally have 4 items at level 30: Muscle Band, Scope, Buddy and Score Shield.
>>48517881It's never been bugged, the stat just doesn't work how people thought it did. It's not a flat 7 percent increase. Basically auto attack speed has "breakpoints" and you have to reach those points to get the stat increased. It depends on which mon you're playing and what level but pokemon like Cinderace basically never reach the breakpoint at most levels and see no benefit from the stat increase.