Interesting have tried numerous systems the last 27 years and always come back to flood coolant.
About 7 years ago to get me out of the proverbial (two coolant motors went down) did some research and went for a Noga Minicool
http://www.noga.com/nogaProducts.php?catID=moco
One thing you don't want on any of these systems is airborne particals and hard not to achieve with any flow of any use. When its airborne its very dangerous, be careful.
First used on lathe, ok for parting and general turning reasonable but drilling, boring and reaming forget it. Have numerous specific tools that only work with coolant, the mister could not feed through to the cutting edge boring, sprayed in the bore not enough. Same boring job I have no problem with flood coolant.
Though it does cool to an extent the tool and some of the job, its no where near enough, proof of the pudding was literally only turning some Titanium bit above finishing cut went ok ish but caught fire in the swarf tray, that says it aint cooling the job.
Also have many tools with thru coolant which can only be used with flood feeding in to rear of tool via flexy silicon tube.
Misters on mills far better than lathe work as long as you don't push it, found far easier and quicker to use a squeezy bottle and not constantly powering up the compressor. Economy don't come in to it, cutting fluid can be costly to buy in 25ltr drums bearing in mind used daily it will last at least 12 months, it evaporates more so in summer needing around 2ltrs a day top up with water.
Max air pressure showing signs of going airborne with Noga valve half open was around 30psi regulated no where near enough unless milling slots where coolant would build up like flood coolant would and surface light milling.
In last 7 years used it twice, says it all and I use lathe and mills all day long every day even make aluminium stocks from solid, just my take.
The Pros where repetition involved and cnc work use higher pressure misters with larger multi nozzle setups usually in an enclosed container.
