I for one use it quite a bit. The same census sheet on some genealogy sights are not that clear. Heritagequest is much better.
1930 census on HQ can only be used on the BROWSE. It can be time consumming, BUT it sort of forces you to go sheet by sheet and look around in that census district at the people living there.
When I was looking in the PERSI and ordered some of the articals available, THE QUILL Newsletter was one of the genealogy magazines that had information about some of my surnames of interest in SC and Mississippi. People who have written articles about their families and, articles the editor has written about is in this newsletter. You must be a SC Genealogy Society member in order to receive this personally for South Carolina. It is worth it. PERSI also lets you know what library may have a periodical of interest, example, The Indiana Library.
There is a lot HQ has to offer, but so far I still am using Ancestry at this time because, family has found my postings and we made our connections. More people have responded to family trees because of TV advertising. The TV program does some good by making people curious about ancestors.
BUT FREE for the same information is always good. Maybe a little more work, but good.