My favourite colour change to do live would be the Twirl change as its just so simple and confusing of course with the Snap Change and Erdnase. And my favourite impractical would be Cardini Change as I can never ever get the angles right.
I have learned it, it's fantastic and I do use it just not in live performances, I don't feel comfortable yet as I feel that if I can't nail the Cardini live then I won't with the Popcorn change.
Honestly, I've been doing the cardini change for so long that I don't have any issues with angles any more. My only issue is performing it for a group of people. Other that that, I love it! If I am performing for a large group, then I usually use the duck change.
Clipshift for pratical, has the benefit of using just one hand which just adds to the wow factor, tony change has a nice change the be kind change, which looks pretty cool although I'd probably not use it in a performance
My favorite change to do in live preformances, is the shake change. Although very simple, if done correctly, it can be very convincing. My favorite impractical change, for obvious reasons as already stated, is the cardini change.