I can take them or leave them. I spent about £200 on mine and would prefer that to claiming on my insurnace if I ever hit a post. But before I had it, I wasnt desperate for one, nor do I miss it when driving cars without them. As with ioneabee - I use all the tools I can to do the job, so if its there use it, if not, no biggie.
However, not so much a dilema for new 370z owners as reversing cam is now part of Connect Premium, which is well worth the money with or without the camera.
If you have a 2010 car then a cam can be fitted quite easily and is nice to have, just depends how much cash you have kicking around. I'd be worried personally if a few hundred quid breaks the bank in a 370z owners mind as they are expensive cars to run! Will cost you way more in insurance should you bump into something