? about generators and controllers etc..

ive been growing for awhile but never have used co2,im ready to step it up.im going to buy a co2 generator(cap gen1 eletric/starter) .for the controller i was looking at a cap air3 its about 180 dollars (most controllers cost more than the generators)its supposed to turn the co2 on when the lights are on and off when off.but do i need something to measure the co2 ppm like a regulator (do tanks only use regulator)or does the generator have a ppm control on them?and are there generators that come with some of this stuff because the the one im looking at is about $350 the controllers $180 and if i need something else $?,its adding up pretty fast so are the generators that $600 to $800 better because more control with it or more burners?any suggestion for a lost grower?

Tanks use regulators... You can get an electric CO2 regulator for pretty cheap, put that bad boy on a timer, and set the output level, and you're set. Probably the easiest configuration, and the tank refills are usually between 20-35 dollars for a 20 pound tank.