I wouldn't say mine was life-changing although it has had an impact on me and, for a long time afterwards I carried the negatives of that. But my c-section was dreadful, a lot went wrong during it and I had complications both during and after. This is why you sign the consent form because it does carry risk as all childbirth/operations do. They are minimal, but they do occur.
Personally I think they are GRIM but I've read lots of positive posts on here that make me think that I was pretty unlucky. I have five friends who've all had caesareans (emergency or scheduled due to complications - none of us 'chose' them and we all would have preferred a vaginal birth) and they all agree that they're pretty hard in terms of recovery. Certainly none of us were breezing about a few days afterwards and all of us were surprised at how limited we were for two to three weeks afterwards.
I think if you expect a fair degree of discomfort and pain and a slow recovery (i.e three to four weeks before you're up and about and feel yourself again) then anything better than that is going to be a good surpise. Accordingly, if you arrange help for the first week or so and set things up so you can take things easy (lots of home-cooked food in the freezer, the determined mindset that that housework can WAIT for a few weeks, etc.) then that will help hugely.
I think the comment about 'life changing' was probably meant as an antidote to the "oh my c section was a breeze" stories that are about. Certainly some are but I think it's misleading to portray this as anything other than a major operation that brings with it pain, the risk of healing complications and a good few weeks of recovery. Sure, some people bounce back and are very lucky, but it's not guaranteed and I think going in with your eyes open to the possibilities means that you can get things in order to make the post-caesarean period of recovery as easy as possible.
Certainly if I'd known what mine entailed I'd have taken things a lot easier and probably recovered a lot faster. Knowledge is power in my book.
K