LOVE this post! Thank you for compiling all the options!
I actually saw a picture of City with the long strap on my FB somewhere so I asked SA if I could purchase the long strap when I bought my Gris Fossile City last month in Seoul, Korea. She did say it's only available in Japan- ARGH! Japanese people always get all the good stuff! (I'm still bitter from all the Japan-only bonus tracks in my youth.)
I think I'm gonna try the cheap necklace route first, then if it doesn't work I will try Mautto straps- if I do I will let you know how they are.
Thanks again for this super-informative post!
Is it still available in Japan? Which store? I will be going to Japan end October. I would like to check out those long straps.