If you are running CO2, you really want total control over all grow set points to be able to use it effectively. I think of it like an amplifier, but to an electrical engineer everything comes back to electrons lol. The amplifier can take what you are doing and make it a little bigger, a little faster, etc. But that also means that it will amplify problems or weak spots.
I run RDWC and CO2, and the growth rate is up there with the best of 'em. But if I have a problem, that also means I have less time to react before the train runs off the tracks. When I am pressing hard, I need to check the plants a lot for any sign of stress, and immediately jump on the issue. That grow style is not for everyone. Not sure if it is for you.
It DOES force you to climb up the learning curve pretty fast tho if that is what you are going for.
Another analogy - you can put NOS on any car. But only the ones that have been built to take it will not throw a cam or something when you use it.
In terms of the cost vs gain - I have yet to find a cheaper way to immediately impact the gain in the plants. I average $20 in CO2 used per grow.
So yeah, good and bad.