I think the sedentary life of a bristleworm accounts for its shelf life. They really don't expend a whole lot of energy in their daily sludge prospecting.
They're very interesting animals when handled. They don't sting as much as they assault you with their bristles. If you've ever been *****ed by a cactus you have the general idea. The spines of bristleworms are almost microscopic in diameter, and instead of a single puncture site, you have hundreds of them in your skin. It often becomes infected, leading to hot, red, inflamed fingers, or wherever the wound is. As far as I know, the spines are impossible to remove, resulting in you having to just tough it out.
As tank creatures, they're really not bad to have, just don't handle them.
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90G display tank. Kent Phos Reactor running carbon and ROWAPhos, Coralife 225 Skimmer. Wet/Dry converted to 10 Gal Sump w/ auto topoff float valve connected to Typhoon 5 Stage RO/DI. Little Giant inline (external) return pump. Coralife 2x150MH, 14K + 2x96W PC Actinics, Ecotech Vortech propeller pump, Hydor Koralia #2. | 
