Here in Australia, standard practice seems to be using C16 breakers on outlet circuits (I know my home has them). In some other buildings we even have C20 breakers (or British-style rewireable fuses in older installations) -- plus a 20A outlet (admittedly rare in residences) that also accepts our 10A (and 15/16A) plugs!
(As if we weren't "living on the edge" enough already...
I also happen to have downloaded a flyer for Prysmian's "Flat Xtra" cables, which calculates their route lengths based on "mean" instead of maximum trip currents.
)
Considering that a B16 breaker is the most that proper practice would allow with 0.5mm^2 wires (AFAIK), and that C-curve takes up to twice the current to trip magnetically -- I'm
not that impressed with the Australian way.
Personally, I'd then stick with up to a B16 (or C8) if there's any chance of plugging in a 0.5mm^2 flex; if I could be confident of 0.75mm^2 (or my suggested 0.63mm^2) as the smallest that will ever be connected, then B20 or C10 would also be fine.
For lighting circuits, on the other hand, C-curve breakers seem sensible...
