Example....a short time back a friend bought a no-name English hammer gun. Nice looking good condition gun...nice barrels.

The day I looked at it....I cocked the hammers a couple of times (both hammers felt like you needed a come-along to cock them...kinda like an old Remington hammer gun).
I commented that if I were you I would send it back before the 3 day inspection is up. Yesterday the left lock decided it wasn't going to fire.
A SxS is only as good as it's locks.