All good points, one's CCW has to be spot on reliable/dependable.
But I do have to add, I'd still rather actually own/carry a pistol that is very likely reliable instead of NOT being able to carry another potentially slightly more reliable one simply because you cannot locate/purchase it ANYWHERE.
There are options other than just these two of course but this thread is specifically about them (ie: Nano and Shield).
Heck, I'd rather carry a Taurus PT22 versus NOT carrying an M&P Shield that hasn't even been manufactured yet LOL.