you're much better off with a 36" hood. it's not so much about avoiding damage to the cabinets as it is about capturing all the smoke/steam effectively.

Edlakin is right, plus if you look at BlueStar's online installation manual for their ranges, it clearly says that every range needs an extra 6", so a 30" range needs a 36" range hood. We ended up getting a Ventahood because it's 300cfm hoodfan is suppose to be the equivalent to 450cfm, and I couldn't put in a 600 cfm fan without spending thousands on installing a make-up air system.

From the manual:
VENTILATION
Proper ventilation is highly important for good operation. This appliance must be installed under a properly designed canopy hood. The hood should be six inches [150 mm] wider than the appliance. A strong exhaust fan can create a vacuum in the room. For proper air balance work with your dealer and/or contactor to properly size your hood and its exhaust fan. It is recommended that your exhaust hood be powerful
enough to move a minimum of 300 cfm.