I have a Stew Mac gun. I bought it thinking it was special for guitars, but it is just a production sized syphon gun.
Now, would i recommend one...it sprays good, has all the different adjustments,cleans well and will do the job great depending on your skill at spraying. But..., i got talking to a fella at the paint shop where i just bought my last batch of 2k poly and he recommend for spraying guitars, a small gravity feed gun(touch up gun i think he called it) which comes with a 100ml tank, but, you can also attach the measuring cup which has all the mix ratios printed on the side. Why did he recommend this? Because the size of the objects we are spraying are small, you can mix up smaller amounts of paint and have less waste. 2k is going to go off even in a sealed container once mixed, so with my production gun i have to mix up around 150-200ml just so it will spray smoothly usually leaving some left over paint. Fine for nitro though as you can leave it in the sealed gun overnight for your next spray session or, tranfer it back to a spare can.
As for asking and giving advice, take what you want from posts, when i read this forum i skip over so much BS and take all the useful parts. If someone like Drak is giving finishing advice, i would be listening.
I basically think the original question has been answered. I will agree that really Pro jobs aren't sprayed with hand sprayers though, guns will always offer better finishes, and yes that does come from experience.
John, if you find a decent cheap setup, make sure you post your findings for other people on the forum who are in the same mindset.
Cheers
Chad.