I guess you'd rather have a democrat than republican
"When choosing between two fans of murdering the unborn, what's the difference?"
First realize that should the SC rule against Roe vs. Wade, most states will continue to allow abortions. That is generally understood.
Except for SC appointments, most Presidents have little impact on that single issue.
So the difference would be all of the other issues.
Many voters do consider more than one issue. National Defense would be an example of another issue, where the Republican would hopefully be stronger.
Spending, taxation and immigration would be other examples.