I took a year's maternity leave, went back to work full time for a bit - and hated it. Hated the fact I was spending 8 hours a day working, plus up to 2 hours commuting, and seeing so little of my son. Hated the fact that I was supposed to just slot back into my old working life and pretend that I hadn't changed - and what a massive change it was - and that my priorities weren't completely different. I also realised I didn't actually like my job anymore, so there was an added impetous for me to leave.
The massive benefit of being a SAHM, for me, has been slowing down the pace of life a bit (from the frenetic speed at which my life seemed to be going in my career-driven 20s) and just 'hanging out' with my boy. I like the fact that there is no massive rush in the morning to get anywhere. I like the fact that I am the lucky one who gets to take him to the park, swimming, toddler groups, nursery etc. We have a lot of fun together, lots of little adventures, and nobody knows him better than I do. I see him all day every day, and see how quickly he changes (amazing!) and for the most part, it is a pleasure and a privilege. He is 3 next month, and I will NEVER regret having spent these precious first few years with him. I feel very, very lucky.
Another personal positive is that over the last few years, with time to reflect and work out what's important to me, I have decided on a complete career change for the future - something I feel really passionately about, and which will fit in more flexibly around my family life. I don't know if I would have reached this decision if I hadn't have had some 'time out' from work to really mull things over.