I've been in the same boat as e57, and have had to do it both ways.

I prefer electrically held contactors to shunt trip C/Bs.
1.) The breaker supplying the power to the trips themselves might get turned off (even with a lockon) and go unnoticed [Linked Image]
2.) Breaker space is usually at a premium in kitchens, never seems to be enough. The shunt trip needs an extra pole space.
3.) Contactor = less $$, and easier to get.