Atmos what speakers?

[mgv8]

Hi All
My amp can do Atmos and there is a lot more content out there with it. So the easy option would be up-firing speakers but I can fit in-ceiling ones. Two questions:
Is it worth doing all the extra work for the in-ceiling setup?
Can I get away with 2 speakers or is 4 the way to go?

Thanks for any input.

[mgv8]

Thank you