Having both nodisarm/nobreak is paramount to a shield ded paladin.
No shield means dead paladin. I've had three hero shield dedicants
and there is nothing like scratching that off your list, not having
to carry extra shields, pay for shields, or worry about an offhand disarm
or weaponbreaker or grapple or whatever else there is out there to
knock down your shield.
A paladin with a nodisarm-nobreak shield and a light cursed weapon
is not as easy to get set up with as it sounds and makes life a hell
of a lot more convenient in combat.