I’ve had many black caps. Just like all birds, each individual will have their own personality, so it’s hard to generalize. I’ve had maybe 3 (out of 25 or 30) BCC that were as sweet as the best GCC can be. But generally I have found BCC to be a mite more fractious. Maybe a bit more temperamental in nature. They’re gorgeous and most of the time they know it! The majority of them preferred bird company to human, and when the hormones hit things can get rough- but that’s the same no matter the species. They have a reputation of being “quiet birds” but I think that’s just a made up marketing/selling point- compared to any Aratinga, for sure Pyrrhura are quieter but nobody kid themselves, Pyrrhura can squawk up a ear piercing storm when the notion strikes. Many conures can be bitey little angry bats, and BCCs are no exception. Care and caging is the same as for a GCC. Lifespan pretty similar as well.
Pictures required if you have a new addition!!