Shove her in the pop top lolI went the 120cm RIB, as id rather have smaller cupboards than be crammed in with my wife.
We were worried that the bed would be too narrow but I actually sleep better in the van than I do at home.
I agree with your thinking; the 8cm on the bed in negligible but makes a big different to how you can use the side storage cupboards.I've spec'd the 112 for ours as when comparing you didn't notice the difference between the beds a great deal however you really noticed the lack of storage in the narrower cupboards. I also figured if I'm taking the other half I need to account for all the rubbish she brings. Less room for scatter cushions.