See if you can try different types before you buy is one piece of advice. Also make sure you can get it serviced locally. Another question to ask yourself what sort of diving do you think you want to do. When I bought my first regulator set I had completed the PADI equipment specialty course which helped no end in deciding my choice. I knew I wanted to go deep and in colder water than here in the panhandle, I also new I wanted a DIN rather than yoke connection. In the end I bought a Aqualung Titan LX Supreme which is a balance diaphram regulator. I’ve been down to 130 ft and it allowed me to breath the same as if I was at 30ft. I’ve also dove with it in Scottish water where the temperature was 44F.......