Glad to hear it wasn't a catastrophe... even though it was a mess! We've got some H3R halon ones at the shop and in our cars. Halon makes no mess, but not cheap. I guess cheaper than the hours spent cleaning up the powder kind. Halon is no longer made thanks to EPA regs, so these are all reclaimed units, causing the price crazyness. Interesting FAQ about the stuff:
http://h3rcleanagents.com/support_faq_2.htm#q1