Thanks everyone!
Splintergroup - the one he worked with had the right personality (although she does also sniff inappropriately!)

Dave - my husband got a glucose sensor and dropped off on her training.  She still does alert sometime (thankfully he doesn't have too many lows).  

Ron - you are so right that working dogs like having a job.  She was really relentlessly when she sensed he was low -her response was to put her paw on his arm.  

Mike - sounds like you have an interesting pair!!  Lab would be sad as in real situations, only get rewards when the human is actually low.

Oldrivers - she is a faithful dog and may be the most "in touch" with us.  Always knows if someone is sad or upset.  

Pottz - dogs are amazing.  She would actually beat his technology with alerts before it would show up on his monitor.  

GR8HUNTER-dogs have some real gifts!