Speaking as someone with little to no experience in this area (and hope never to!), this magazine article that I came across a while back seemed quite informative:
http://vmemag.epubxp.com/i/46635
(starts at P.62)
Also a question for someone with experience in this area: In the US, Halon is readily available. It's not manufactured anymore, but there are large stocks available and legally offered for sale, so most common options here are:
Halon (two types: 1211 and 1301)
FE36 (halon replacement, although seemingly not as efficient)
AFFF (aqueous foam)
and some others, but broadly falls along the lines of Halon, halon replacement, or foam
If I decide to plumb in a system, go for Halon then? any ideas about optimal size - as big as can fit or...? (Halon is sold by weight - 3lbs, 5lbs and 10lbs are common, whereas foam is sold by volume 2.25L or 4L)
Regards
Paul