Hi, I understand MIFARE cylinders and NTAG chips used in NFC rings share the same NFC frequency (13.56 MHz) and the same ISO/IEC 14443 standard. I don't understand the limitation, especially as NFC ring say in their FAQ:
"All door locks with NFC (ISO14443) should work fine."
So maybe the cylinder you bought is not ISO-14443 compliant?
If you are using RFID tag reader/ writer that is not working well and not happy with that I think that you should choose other company RFID tag that easy to work with NFC ring. Hence there are many companies that provide top quality RFID tag online. For more updates visit on RFID Loyalty tag.
Really, If you are trying to change your simple door lock and want use electronic digital lock, I will say. You should try once www.sato.sg of primesource.me. These companies are providing top quality digital locks for home and business.
If you are really looking for a locksmith i suggest http://locksmithtoronto365.com/. He installed my Kwikset system. Its good and reliable small company. Now i`m looking forward to smart Samsung lock. I recommend not to install yourself expecially when the lock is pricy.
Having locks on zipper luggage is just of annoyance to yourself- other then maybe preventing it to open up by getting stuck somewhere- zippers are extremely easy to open with a normal pen and wont stop anybody if they really wanted to get into it without a trace.
I'd use this kind of lock for a outdoor shed or maybe a steel-cable bike lock :)