Hi David, I bought a front wheel and tyre to put in my boot when I got my 2016. Although it does fit in the wheel well it still sticks up a fair way.The main issue I found with it is that it is very heavy to lift into the boot and out again when needed. I ended up putting it in my garage and buying a slimmer version (which is well discussed on the S550 forum as the gnome spare). That way the slimmer spare will fit better in the wheel well, although it still sticks up a bit and is easier to get in and out. As long as it gets me home where I can swap for the proper size spare in the garage all will be good. I bought a boot carpet mat and you can hardly notice any rise in the floor with the slimmer spare wheel in there.
