Far as residential sprinklers are concerned you'd play hell selling them here. How much sprinkle are you going to get out of a 5/8 copper service line anyhow?
Enough to save your life if a fire started. Single family design is generally based on life safety, giving occupants enough time to get out. Design is based on 2 heads operating. Demand is usually less than 30 gpm, and you need a 10 minute supply. 300 gallon tank w/ a pump to get it delivered does the trick.
As of 2011 all single family homes would have fire sprinklers if jurisdictions adopt the international residential code and don't exclude that part. It will eventually be adopted everywhere.
Most people think they could get stuff and get out if their home was on fire. Whole homes take just a few minutes to be totally burn down. Or worse, flash over after 2 or 3 minutes and have temperatures over 2000° melt all their switch-plates and wiring, along with everything else.
Its tough, like seat belts were.
Okay, stepping down off my soapbox,,.,.,.
Chilly