If you decide that a .380 has enough firepower for the circumstances that you are likely to encounter, and if you determine that it is not necessary for you to carry one in the chamber, then an operable M1908 will serve you as well as any modern .380.
Choose your footwear to match the use. Same for choosing firearms. We don't all need to carry a .44 Magnum, or whatever the biggest gun we can carry concealed may be. I usually carry my M1908 Vest Pocket .25, because it fits the need I'm likely to have for a gun most of the time. I rarely carry my DA Government .45 unless I know that I'm going into a "hot spot".
I would note that there are self-defense .380 loads that are nearly the equal of standard 9mm loads (as measured by muzzle velocity and energy). I don't know how well they perform (FTL, FTF, FTE, etc) in the M1908, but I'm told that the M1908 would have no problem handling the power.
Personally, though, I'd never carry a M1903 .32. A hot rod .25 round equals a .32 standard load, but a hot rod round of .32 does not equal a standard .380 (at least none of them do that I have seen). If there's one out there that does, let me know. There's a M1903 at the LGS that I might buy if I could get a .32 round that comes close to a standard .380.