I would go the GCC. They are such little balls of energy, I have a male and female (they will eventually be our breeding pair in 4-5yrs time) and they are so sweet and so hilarious. Absolutely besotted with each other, but Tika (OH's female) is also in love with my OH. We've had very minimal nippyness since the first couple of days we had them, now that we have gotten to know each other we have no issues. Tika will occasionally grab my finger if I offer treats thru the bars of they're cage, but it's nothing compared to a proper bite from her! I haven't had a full on bite from either of them since the first week we had them, we've had them since the start of January. Our first GCC never bit anyone for the 4 or so months we had her, not even tiny little 'tastes', all she ever wanted was to cuddle and hide in hair. If there was any sort of gap anywhere she'd go and hide there. We didn't actually realise how entertaining and hilarious they were until we bought a pair, I could sit and watch them play for hours.
Rory (my male) is such a good talker, he seems to be learning a new word or phrase every 2 weeks or so! He can say:
'hello Rory'
'hey Roreeeeee!'
'hmmmm step up!'
and
'come 'eeere!' (which he actually manages to use in context!)
You just have to know how to listen to them to start off which and encourage them, his 'hello Rory' actually started as whistling the tune, and with encouragement from us (and a few stern words to the OH about
not repeating the whistle, he says the actually words now), and they have the cutest little gravelly voices!
He can also make a variety of noises, such as kissing noises and me sniffling
Tika is much quieter, she makes a quiet kissing noise but that's about it. She is so so so smart, you can seriously see her thinking things over in her little head. Much smarter than Rory, but she has issues with hands for whatever reason. Same breeder, has had the same handling as Rory, and we're always consistent with what we ask of her, she's just so scared of hands. You have to get her to stop flying around being 'scared', get down to her eye level and hold your finger right up infront of your own face and ask her to step up before you even offer your hand, and then she stick her foot right out, happy to step right up, but heaven help you if you then ask her to step from one hand to another!! Just goes to show that they all have different personalities!
I don't know anything about Moustache parrots, apart from they're very cute!
Whatever it is that your adopt, you have to post pictures for us to see! Good luck "_