We purchased Morgan, our TAG, from a breeder who was recomended to us by my husband's family. We were able to visit with them and Morgan a few times before bringing him home. He's very confident, friendly, inquisitive, and outgoing. We couldn't be happier with him.
The pet stores in my area do not sell medium or large parrots. We did purchase our sun conure from our local pet store though. Stewie is very affectionate, friendly and has a fantastic personality. We could not be happier with him. We also visited him several times and formed a friendship with him before bringing him home.
Both breeder and store hand fed the birds and spent a lot of time playing with them and handling them. They were both happy to answer all of our questions and give us great advice. Both took excellent care of our boys. They did fantastic jobs.
I feel that us being able to visit both birds while they were weaning, and being able to interact with them often enough that they reconized us and showed signs they were happy to see us was key in making our transitions home super smooth. If you are able, I definately recomend pre-homecoming visits.
Good luck with your search.