My Kyra is a rescue - I got her from a breeder. I had done ALL the research and I still wasn't prepared. I was told that she was given to the breeder due to aggression towards the spouse of the previous owner. She was never aggressive with my family (thankfully) BUT was aggressive to my littles (my parrotlet and my budgie - both of whom she injured through cage bars!). My first go with her I had her for about 5 months. We were in the middle of moving, she had just attacked my littles (one had an injured toe, the other an injured beak). I was having to keep her caged almost constantly as she had also dive bombed my big cat who then grabbed her (she was fine, but I was NOT).
After all that, I felt really defeated (understatement - many many tears) and rehomed her. I regretted it. If I had held on just a little longer, we would have been all moved, etc. I can't turn back time. A year and a half later, the woman I rehomed her to couldn't keep her anymore. She has several birds and working long hours, Kyra was stuck in the cage with no enrichment. I took her back in a heart beat. It was the best decision I have made! She obviously remembered me. She is glued to me unless she's in her hanging play gym - then she won't go anywhere else unless I walk out of the room LOL! She is still very loud, but my ear sensitivity is my issue, not hers - she's being a normal parrot. She will 'yell' at the cat and dog now instead of dive bombing them. She is settling in more and more, and I'll soon start clicker training with her to ensure she comes to me when I call her. IRN are stubborn, training is very important. Always give them time to settle in, time to get used to your routine, and time to adjust to life with you (not the same as settling in). My big mistake the first time was allowing her to free fly from day one with not enough training.
Because of her background, Kyra is more of a challenge than a hand-raised baby. That should be a part of how you decide on one - do you want a hand-raised baby that will be completely human friendly, or a rescue that will take work? I can't speak on hand-raised ones other than they seem to talk better and are more responsive to training. Kyra requires a great many incentives for training lol and hasn't spoken yet, but will bark like my pup LOL! It's honestly hilarious and I hope to catch her on video doing it.
I hope that helps! The link shared by aooratrix is definitely a great resource for pros and cons. For me, it was much more informative then most sites I found.