my daughter's dad had a temper tantrum when he found out that DD was going to have my last name. I doubted myself multiple times, I mean up until the minute that I had to fill out the birth certificate in the hospital. He was angry. He threatened to terminate his rights. He said that he wanted nothing to do with a child that didn't have his last name...lots of hurtful things toward me, about me, and about our child. But at the end of the day, I did what I felt was right and fair to my CHILD. If down the line things changed and she decided she wanted his last name, then I would honor her wishes and get it changed. I figure it's easier to change TO his last name, than to try to change FROM. Because he'd have to approve the change from his last name.
Do what you feel comfortable with regardless of anyone's opinion.