If a couple extra dollars on okay, There is a good way to add safety as well as save gas and keep it all very stable.
One big point on saving money on the reg setup is to go with a single stage reg as they are lots cheaper. The downside of some of them is that they can lead to an"end of tank dump" (EOTD) which is very serious as it can dump lots of CO2 into the tank and kill all the fish, making many folks very nervous about using single stage regs. So one way to get multi-purpose is to add a PH controller but save some money by going to the cheaper reg. Total may cost a few dollars more but you get some other bennies at the same time.
Off gassing is not an issue which concerns me terribly as the actual gas is very cheap, but I do like the tank to stay stable, even though nature may not keep CO2 that way. I breed African cichlids and they tend to be high dollars folks which I like to give the best shot possible and stable is my main point to keep them healthy!
A cheap "beer reg" for $50-60, tied to a controller which cuts the gas on/off depending on the actual level does a good job of giving me safety as well as making it much easier to monitor. NO bubble counting needed!! I find no need for bubble counters which don't work for large gas flow on big tanks nor flowmeters, when I use the controller and just look at the number on the front!
Just an alternate view from a guy who doesn't like to work much!