the meaning of the sentence

[Unregistered Lina]

Hello

Would you help me understand the following sentences?

#1 We're all set.
#2 We're all ready.
#3 We're all done.

I think you use #1 quite often. How about #2 and #3? Do you use them?
If so, what does #3 mean? Does it mean the same as #1? Or does it mean" we have finished something?

Thank you.

[Tdol]

3- means that we have finished
I'd use them all. I think I'd use 1 more than 2.