Flash shoe woes-- does size matter?
The X10 is hardly the hardened, durable camera that you think it is -- relatively speaking, compared to pro-sized DSLR bodies targeted at sports and photojournalists.
Having said that, I wouldn't even consider carrying a large flash attached to such a DSLR body all the time, in a non-hardcase bag especially. It's just a matter of physics. It is hard to reinforce such a small contact point as a flash hotshoe; even if the hotshoe and camera body were a single, reinforced metal mold, the flash itself would still break at its hotshoe connector if given sufficient stress.