[guappa]

Not like whatsapp works decently if you have 2 sim cards… you can use 1 phone number per phone and the other one is just ignored.

[Yeri]

Fair enough, but it keeps working with your (old) sim. iMessage deregisters every time, and it stops working for me. And you have to head back in settings and register again.

I've found the process to be very buggy and rarely works.