I have the Road ID bracelet and anklet. I wear the anklet most of the time, and the bracelet much like everyone else: it lives on my helmet straps and I put it on every time the helmet goes on.
My ID were made before the interactive one was available, so they have my doctor's 24-hr number on them so EMT/Emergency room folks can call to get my medical records, insurance info, etc.
Road ID is a great company, I have absolutely no complaints about them. Their customer service is wonderful, and once they gave TE members a discount (for a month). If someone who hasn't bought Road ID wants to take on a project, they could contact the company and ask for another month-long valid discount code so those who don't have them yet can order them cheap.
Trek420 has the dog-tag version and says it's very comfortable. She puts her old ones on her dog...
"If Americans want to live the American Dream, they should go to Denmark." - Richard Wilkinson