Mike, With the HVLP guns you need to use larger fittings to get enough air flow with even the proper compressor in order to make them work properly, at least on the air hogs. Some of the better HVLP guns such as the IWATA will use less air but still way too much for a compressor that small. There are several low volume guns that will work that do an excellent job, I have not used that Astro myself but I have heard some good things about it and it will not use nearly as much air as the guns you are looking at.
FWIW, I have one of those Finex 300 guns that I picked up at a yard sale a while back and I am not very impressed with it. I asked about that thing here back when I got it because the pattern was way too narrow and I wanted to know if this is normal, seems that it is.