A family member of mine has a health issue. Not being diabetic(many EMTs assume that before reading these things when they see them) if she ever falls into a crisis it is important that certain medications not be administered so the correct ones can be once she reaches an ER. The bracelet, or sometimes the necklace she wears, have that engraved on them. You almost never really notice when people are wearing these things unless someone important to you has one. Then you notice everyone that wears them. They are good for what they exist for.
In years past having an allergy to a medication, or a condition that could spiral out of control if mishandled was a real risk. In the world of today, it borders on irresponsible to not have something to speak your special needs in event you are unable to. And with the various types of materials that they are made out of surely you can find something that will work for you no matter what personality or conditions you have.
Use and budget:
If you have a condition, you should have one.
Stainless steel is durable and tough and not too expensive. Many styles to choose from. Get one that fits who you are. Or get more then one and change them with your mood.
I recommend according to whether or not I use a thing or would recommend them to my own family members. Reviews are important but you should always eliminate the very best and very worst and see what else people have to say. Look for facts in the reviews instead of feelings.
Why should you get one:
Here are some that you can choose from. I personally do not need one but have family that does and I know the importance. Knowing from personal experience, if you need one you should have one. There was a car accident. My family member went into a crisis and the EMTs though she was just high on something and were prepping to treat her as such until they read the bracelet. Fortunately a close friend arrived at the scene and grabbed her emergency dose from the glove box and injected her on the spot. She recovered to the point the EMTs released her to ride to her doctor with the friend.
Yes, if you need one, get one. If you don't want one from this list, that is OK. They are made out of gold, or silver, or steel, or other metals and various kinds of plastic now days. Even if you get one you don't like, you can always get another. Don't die because you want to avoid risking money to get the wrong one.