In our case we both kept our last names. Why change her last name when that’s who she’s always been? Really simplifies things as far as paperwork goes. Also - LPT: when you have different last names you can get double the introductory offers on things like internet packages at home. Just sign up under one name, cancel when able, sign up under the other. They don’t know you’re married.
I mainly ask, because when I worked in an armory there was a dude named 'GonzalezLamas-Suarez' whose name I had to handwrite on a very small line every single time I signed him out gear. It was the smallest font I'd ever seen on a uniform before.