I'm looking to buy my first regulator and would like some input - which are good, which aren't, single/double/triple gauge, etc.? There appear to be a lot of options online. At the present time I only plan on having one keg hooked up. In the future, who knows. Is it better to have one primary reg and buy secondaries as needed in the future or buy a multi gauge now. Somewhat on topic - is a steel or aluminum CO2 tank preferred?