I’ve got 19 total (16 unique). According to the app, I’ve opened 298 booster packs with stamina. Looking at the opening rates, I think there’s ~3.84% chance of pulling a ☆☆+ in a pack - I should only have 11/12 cards, so I’m doing better than expected, but I got some from wonder picks.
Yep, Pikachu ex was really useful for me for getting through the Blastoise solo event a week or two ago