The 1HP compressor is just a little louder than my vacume cleaner.
No taiwanese or chinese copies are ever as good as the iwata versions, I know this from experience. I have bought several to try and they all are collecting dust right now. Their needles have much more in the way of machine marks, their trigger action isn't anywhere near as smooth, and their nozzels aren't made of the same alloy. This leads to much clogging and tipdry.
For a hobbiest they might work okay for basecoating, and many do use them well, but it is a little inaccurate to say they are the exact same.
Iwata also doesn't produce airbrushes in china or taiwan, as far as I know. I'm not an iwata fanboy or anything as I have german airbrushes, and badgers, and a paasche, so I'm not speaking out of a bias or anything. I actually think my new harder and steenbeck airbrush is one of my favorites right now, and it's not an iwata.
I wouldn't change your order. You'll be happy, and the lite version will work every bit as good as the tank version, and it won't pulse air because it's an actual piston compressor motor. It will just run while you're using it but it will shut off as soon as you stop the flow of air.
Cheers