Whitby 42 Brewer Sail Boats

I am looking to install an automatic fire extinguisher in my engine room. Does anyone know the square footage to determine the appropriate model?

Also does anyone have this type of system - what are pros and cons
Thanks
Andy
Whitby 42 Maine

Last year I spoke with a supplier of automatic fire extinguisher for my engine room. He said I would need a mininum system to cover 200 sq. ft. as the engine room is open to the fwd and aft bilges. I installed a Fire Port and bought two large extinguisher instead. The best $10 you ever spend on your boat. I may add second Fire Port later.
see web site of more info
www.marineeast.com/a_sch/sch_det.asp?cid=13&pid=13_01

Cheers
Derek and Darlene
Ocean Dove