You're right. It is not a pissing contest. I didn't mean to make it sound like one.
Some of us would love an hour or a night free, or even a few days, or is that just me? 
Others are well jel of the sahms who get so much time with the kids.
I proved myself shite at the full time mum thing. V shite. Judging by how knackered I am with child free days and no actual work I'd be shite at being a full time working mum too. But I think that we all have our doubts whatever the situation, and make do.
And it's hard however we manage because, let's face it , we're trying to bring tiny people into a world full of obstacles, and doing our best to make them into fully functioning beings despite the obstacles. Which is no easy task (look at how our own parents failed and succeeded in varying ways!)