Spraytech here is the man when it comes to body work and paint so what he says is most likely true. I know he is a Iwata man and swears by them. He is right, those are all low end guns but out of the 3 I would probably go with the Devilbiss Finishline 3. If you plan to do this for a profession I would suck it up and buy a expensive gun but if just for a hobby then you may get by with one of those guns. I am not professional here by any means but do know what is high quality and not. I see a ton of people using SATA and a lot swear by them but I think most people just get one and don't try many other guns and just SAY SATA is the best without actually KNOWING.
That's my oppinion anyways....