My daughter's maximillian pionus has never bitten. She is a retired breeder, so that speaks to how special it is to have a bird who just does not bite. She was, however, hand-fed before she was set up as a breeder. I would recommend a maximillian pionus to anyone who is afraid of big beaks. Pionus can bite. I have heard the bite is painful, although I've never had a bite from a pionus, and I've handled several. It seems, in general, that the males are more likely to bite if one is going to become a biter, but any female can bite or even become aggressive. Maximillian pionus females generally do not become aggressive. Daisy has only been with us about a year. She only said, "good morning". Then, last week, she started to imitate my daughter saying three or four different things. I don't know if this will keep up or not. She had been the only bird in the house to have only one phrase, and suddenly she has shown that she could imitate quite well if she wanted to. The gal who had her as a breeder told me that her mate used to talk a lot. She said sometimes if one bird in a pair is a dominant talker the other won't talk much even if it can. It will be interesting to see how this develops. My own senegal CAN say many things, but she talks very little. She is quite clear when she talks, and she talks only in context, but she seldom talks.
To me, a maximillian pionus is a small bird in a big body. I know that sounds strange, but that is the best way I can describe Daisy. Then and again, to me, a parrotlet and a green cheek are big birds in a small body. Since you seldom get bitten by your parrotlets because you find it easy to read their body language, you would probalby seldom get bitten by a green cheek for the same reason. I know green cheeks are supposed to be horribly nippy, and my Shira nips, sometimes, but she only pinches a bit, she has never bitten me as hard as green cheeks who don't know me have bitten me. I think you would find a green cheek as adorable as you find your parrotlets. A maximillian pionus female, however, would most likely be even LESS likely to bite you. You could be unfortunate enough to find a nippy one, but it is very unlikely.
Hmmmmmmmmmm, I think you should get all three. Then you will have nine. If you have nine, I can get that English budgie. haha
You have to ignore me, I am nuts, and we have another snow day today, so I am off, and it is not even snowing. (I'm "off" in the head when it comes to birds always, but it is very strange to be off of work for a snow day when there is very little snow.)