I think it all depends on a number of issues if a mist set up works for you or not. For years i just used a spray bottle when machining, be it lathe work or milling. I was put off coolant by the cancer problems some people had with their hands. However with newer and better coolant available I looked at it again. At first I when with the mist set up, not wanting the machines covered in coolant and me having to clean it all up after each session. However I had to machine a number of 25mm slots in aluminium. You will all know that aluminium can be a pig to machine if the work gets hot. And the mist along with air blast to get the chips out of the slot worked ok until the last 6mm or so. I found myself waiting until the material had cooled down allowing cutting to start again. It was also getting harder to get the chips out which was the real problem. So I fitted flood coolant to the mill using an old pond pump and a number of filters. By using a good pressure I was able to stop the coolant flying all over the place and it cleared the chips from the slots with ease. I don’t use it all the time, but it’s a tool I use. As to making my own fog buster, time wise it took less then an hour to complete, once the filter and hose turned up. As I said each to their own.