Tallking about two separate items here, the DAN Tag Plus, which has your personal and medical info on it, and the DAN Gear Tag, which is just a personalized name tag for your stuff.
Yeah, I use the DAN gear tags on a couple of my items so they don't get confused with someone else's stuff on the boat. All dive gear looks the same unless you personalize it somehow.
As for the DAN Tag Plus, I heartily recommend wearing one. Either that, or one of the MedicAlert-style bracelets or SOMETHING that has emergency contact info on it - not an ICE number on your cellphone that someone may or may not be able to find, not a card in your wallet up in the boat, not on the release form you fill out at the dive charter: no, you need those numbers to be
something that would be ON YOU if some other dive boat pulls your unconscious ass out of the water!
There was a good thread about diver ID options a while back:
Anyone wear ICE bracelets?
I say this because of personal experience, see
SB Diver Littlejohn Rest In Peace. Don't let whether the ID tag is "dork" or stroke or uncool or whatever influence you: just get one, and wear it religiously when diving. You owe it to your family - John's family didn't get to see him alive again simply for lack of such a tag.